From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx104.postini.com [74.125.245.104]) by kanga.kvack.org (Postfix) with SMTP id C2C826B00CB for ; Wed, 12 Sep 2012 08:55:39 -0400 (EDT) Received: from /spool/local by e23smtp07.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 12 Sep 2012 22:53:42 +1000 Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay05.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q8CCk0F311403376 for ; Wed, 12 Sep 2012 22:46:00 +1000 Received: from d23av03.au.ibm.com (loopback [127.0.0.1]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q8CCtGXr016568 for ; Wed, 12 Sep 2012 22:55:16 +1000 Message-ID: <50508632.9090003@linux.vnet.ibm.com> Date: Wed, 12 Sep 2012 20:55:14 +0800 From: Xiao Guangrong MIME-Version: 1.0 Subject: [PATCH 0/3] thp: tidy and fix khugepaged_prealloc_page Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Hugh Dickins , Linux Memory Management List , LKML There has a bug in khugepaged_prealloc_page, the page-alloc indicator is not reset if the previous page request is failed, then it will trigger the VM_BUG_ON in khugepaged_alloc_page. It is fixed by the first patch which need not be back port for it was introduced by recent commit. (sorry for that) As Hugh pointed out, this are some ugly portions: - releasing mmap_sem lock is hidden in khugepaged_alloc_page - page is freed in khugepaged_prealloc_page The later two patches try to fix these issues. Hugh, If any point i missed, please let me know, and sorry to waste your time on my broken patch. -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758041Ab2ILMzs (ORCPT ); Wed, 12 Sep 2012 08:55:48 -0400 Received: from e23smtp03.au.ibm.com ([202.81.31.145]:58638 "EHLO e23smtp03.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750958Ab2ILMzq (ORCPT ); Wed, 12 Sep 2012 08:55:46 -0400 Message-ID: <50508632.9090003@linux.vnet.ibm.com> Date: Wed, 12 Sep 2012 20:55:14 +0800 From: Xiao Guangrong User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120827 Thunderbird/15.0 MIME-Version: 1.0 To: Andrew Morton CC: Hugh Dickins , Linux Memory Management List , LKML Subject: [PATCH 0/3] thp: tidy and fix khugepaged_prealloc_page Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit x-cbid: 12091212-6102-0000-0000-00000238A60C Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There has a bug in khugepaged_prealloc_page, the page-alloc indicator is not reset if the previous page request is failed, then it will trigger the VM_BUG_ON in khugepaged_alloc_page. It is fixed by the first patch which need not be back port for it was introduced by recent commit. (sorry for that) As Hugh pointed out, this are some ugly portions: - releasing mmap_sem lock is hidden in khugepaged_alloc_page - page is freed in khugepaged_prealloc_page The later two patches try to fix these issues. Hugh, If any point i missed, please let me know, and sorry to waste your time on my broken patch.