Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751151AbdFBC0c (ORCPT ); Thu, 1 Jun 2017 22:26:32 -0400 Received: from szxga03-in.huawei.com ([45.249.212.189]:6935 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751122AbdFBC0b (ORCPT ); Thu, 1 Jun 2017 22:26:31 -0400 Message-ID: <5930CCBE.4030802@huawei.com> Date: Fri, 2 Jun 2017 10:26:06 +0800 From: zhong jiang User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: Wei Yang CC: , , , Subject: Re: [PATCH] mm/vmalloc: a slight change of compare target in __insert_vmap_area() References: <20170524100347.8131-1-richard.weiyang@gmail.com> <592649CC.8090702@huawei.com> <20170526013639.GA10727@WeideMacBook-Pro.local> <59278B13.4070304@huawei.com> <20170602014549.GA10347@WeideMBP.lan> In-Reply-To: <20170602014549.GA10347@WeideMBP.lan> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.29.68] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020201.5930CCD2.0128,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 15ae7431389f471de4e37aca93c548c3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1726 Lines: 41 On 2017/6/2 9:45, Wei Yang wrote: > On Fri, May 26, 2017 at 09:55:31AM +0800, zhong jiang wrote: >> On 2017/5/26 9:36, Wei Yang wrote: >>> On Thu, May 25, 2017 at 11:04:44AM +0800, zhong jiang wrote: >>>> I hit the overlap issue, but it is hard to reproduced. if you think it is safe. and the situation >>>> is not happen. AFAIC, it is no need to add the code. >>>> >>>> if you insist on the point. Maybe VM_WARN_ON is a choice. >>>> >>> Do you have some log to show the overlap happens? >> Hi wei >> >> cat /proc/vmallocinfo >> 0xf1580000-0xf1600000 524288 raw_dump_mem_write+0x10c/0x188 phys=8b901000 ioremap >> 0xf1638000-0xf163a000 8192 mcss_pou_queue_init+0xa0/0x13c [mcss] phys=fc614000 ioremap >> 0xf528e000-0xf5292000 16384 n_tty_open+0x10/0xd0 pages=3 vmalloc >> 0xf5000000-0xf9001000 67112960 devm_ioremap+0x38/0x70 phys=40000000 ioremap > These two ranges overlap. > > This is hard to say where is the problem. From the code point of view, I don't > see there is possibility to allocate an overlapped range. > > Which version of your kernel? > Hard to reproduce means just see once? yes, just once. I have also no see any problem from the code. The kernel version is linux 4.1. but That indeed exist. Thanks zhongjiang >> 0xfe001000-0xfe002000 4096 iotable_init+0x0/0xc phys=20001000 ioremap >> 0xfe200000-0xfe201000 4096 iotable_init+0x0/0xc phys=1a000000 ioremap >> 0xff100000-0xff101000 4096 iotable_init+0x0/0xc phys=2000a000 ioremap >> >> I hit the above issue, but the log no more useful info. it just is found by accident. >> and it is hard to reprodeced. no more info can be supported for further investigation. >> therefore, it is no idea for me. >> >> Thanks >> zhongjinag >>