From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755941AbdENCfU (ORCPT ); Sat, 13 May 2017 22:35:20 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:57525 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754104AbdENCfS (ORCPT ); Sat, 13 May 2017 22:35:18 -0400 Subject: Re: [PATCH] mm/madvise: Dont poison entire HugeTLB page for single page errors To: Naoya Horiguchi , Anshuman Khandual References: <893ecbd7-e9fa-7a54-fc62-43f8a5b8107f@linux.vnet.ibm.com> <20170420110627.12307-1-khandual@linux.vnet.ibm.com> <20170512081001.GA13069@hori1.linux.bs1.fc.nec.co.jp> Cc: "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "akpm@linux-foundation.org" , "aneesh.kumar@linux.vnet.ibm.com" From: Anshuman Khandual Date: Sun, 14 May 2017 08:04:12 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <20170512081001.GA13069@hori1.linux.bs1.fc.nec.co.jp> Content-Type: text/plain; charset=iso-2022-jp Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable x-cbid: 17051402-1617-0000-0000-000001D110EA X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17051402-1618-0000-0000-000048151936 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-05-13_12:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=2 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1705140036 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/12/2017 01:40 PM, Naoya Horiguchi wrote: > On Thu, Apr 20, 2017 at 04:36:27PM +0530, Anshuman Khandual wrote: >> Currently soft_offline_page() migrates the entire HugeTLB page, then >> dequeues it from the active list by making it a dangling HugeTLB page >> which ofcourse can not be used further and marks the entire HugeTLB >> page as poisoned. This might be a costly waste of memory if the error >> involved affects only small section of the entire page. >> >> This changes the behaviour so that only the affected page is marked >> poisoned and then the HugeTLB page is released back to buddy system. > Hi Anshuman, > > This is a good catch, and we can solve this issue now because freeing > hwpoisoned page (previously forbidden) is available now. > > And I'm thinking that the same issue for hard/soft-offline on free > hugepages can be solved, so I'll submit a patchset which includes > updated version of your patch. Sure, thanks Naoya.