From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751549Ab3KFGAv (ORCPT ); Wed, 6 Nov 2013 01:00:51 -0500 Received: from mailout1.samsung.com ([203.254.224.24]:36280 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750803Ab3KFGAt convert rfc822-to-8bit (ORCPT ); Wed, 6 Nov 2013 01:00:49 -0500 X-AuditID: cbfee61a-b7f836d0000025d7-fa-5279db0f5ae7 From: Chao Yu To: "'Gu Zheng'" Cc: "'???'" , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, =?gb2312?B?J8y35q0n?= References: <000001ceda8d$5b185bd0$11491370$@samsung.com> <5279BA67.4040906@cn.fujitsu.com> <000101cedaae$bb7ed820$327c8860$@samsung.com> <5279D078.8080803@cn.fujitsu.com> In-reply-to: <5279D078.8080803@cn.fujitsu.com> Subject: RE: [f2fs-dev] [PATCH] f2fs: avoid to use a NULL point in destroy_segment_manager Date: Wed, 06 Nov 2013 13:59:13 +0800 Message-id: <000201cedab5$89f0f9d0$9dd2ed70$@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=gb2312 Content-transfer-encoding: 8BIT X-Mailer: Microsoft Outlook 14.0 Thread-index: AQECxHgARzzGwNztGb8VlYqYPj89CQHEf8caAfZG76oC9eybaJt6VeHw Content-language: zh-cn X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrKLMWRmVeSWpSXmKPExsVy+t9jAV3+25VBBpO+mlk8bz/AbHF9118m i0uL3C327D3JYnF51xw2i9aF55kd2Dz+H5zE7LF7wWcmj74tqxg9Pm+SC2CJ4rJJSc3JLEst 0rdL4MroeqNZ0CFScWfDZqYGxj6BLkZODgkBE4npm9pYIWwxiQv31rN1MXJxCAksYpQ40vqK HcL5wShxaephdpAqNgEVieUd/5lAbBEBDYlpU/czgRQxC+xklNi9fgsrRMd6Rokr/0+ygVRx CuhJbJnWDmRzcAgLxEhsuw+2mkVAVaLn4HmwEl4BS4kpr7czQ9iCEj8m32MBsZmBFvQv2sAG YWtLPHl3AepUBYkdZ18zQhzhJjH18zRmiBpxiY1HbrFMYBSahWTULCSjZiEZNQtJywJGllWM oqkFyQXFSem5hnrFibnFpXnpesn5uZsYwZHxTGoH48oGi0OMAhyMSjy8CfKVQUKsiWXFlbmH GCU4mJVEeDfsAwrxpiRWVqUW5ccXleakFh9ilOZgURLnPdBqHSgkkJ5YkpqdmlqQWgSTZeLg lGpgnLP/5AOjOWYb/PKKP2nYnNGbfm0uy9Ysn2Uier4xb9af4ru77p9gkvT5otwq3XVaor9u TTYqY1TOur7LoSJseW+P9Iesg0ly3972KR2r70vtE/+3iv3+zwQlTtOzpoWClkI8ZZEzpjnW R4Zu1lF7fsGbaYrU5dPNHzxmsLD2n+u1YQqcfYBXiaU4I9FQi7moOBEAnhH6PIgCAAA= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Gu, Thanks for your reviewing! Regards Yu > -----Original Message----- > From: Gu Zheng [mailto:guz.fnst@cn.fujitsu.com] > Sent: Wednesday, November 06, 2013 1:16 PM > To: Chao Yu > Cc: '???'; linux-fsdevel@vger.kernel.org; linux-kernel@vger.kernel.org; linux-f2fs-devel@lists.sourceforge.net; 'Ì·æ­' > Subject: Re: [f2fs-dev] [PATCH] f2fs: avoid to use a NULL point in destroy_segment_manager > > On 11/06/2013 01:10 PM, Chao Yu wrote: > > > Hi Gu, > > > >> -----Original Message----- > >> From: Gu Zheng [mailto:guz.fnst@cn.fujitsu.com] > >> Sent: Wednesday, November 06, 2013 11:41 AM > >> To: Chao Yu > >> Cc: ???; linux-fsdevel@vger.kernel.org; linux-kernel@vger.kernel.org; linux-f2fs-devel@lists.sourceforge.net; Ì·æ­ > >> Subject: Re: [f2fs-dev] [PATCH] f2fs: avoid to use a NULL point in destroy_segment_manager > >> > >> On 11/06/2013 09:12 AM, Chao Yu wrote: > >> > >>> A NULL point should avoid to be used in destroy_segment_manager after allocating memory fail for f2fs_sm_info. > >> > >> Though without this patch it still can work well, because if it failed > >> to allocate f2fs_sm_info, the sit_info, free_info... all were NULL, and > >> the destory path(e.g. destroy_dirty_segmap) can deal with them well. > > > > I think it could not work well. Without this patch we may got a segment > > fault in DIRTY_I(sbi) at the following code if it failed to allocate > > f2fs_sm_info memory(sbi->sm_info). Right? > > Yes, you're right. SIT_I generates sit_info from f2fs_sm_info. > Sorry for my mistake.:( > > Regards, > Gu > > > > > static void destroy_dirty_segmap(struct f2fs_sb_info *sbi) > > { > > struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); > > > >> IMO, this patch is still a good catch. > >> > >> Regards, > >> Gu > >> > >>> > >>> Signed-off-by: Chao Yu > >>> --- > >>> fs/f2fs/segment.c | 2 ++ > >>> 1 file changed, 2 insertions(+) > >>> > >>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > >>> index 3d4d5fc..ff363e6 > >>> --- a/fs/f2fs/segment.c > >>> +++ b/fs/f2fs/segment.c > >>> @@ -1744,6 +1744,8 @@ static void destroy_sit_info(struct f2fs_sb_info *sbi) > >>> void destroy_segment_manager(struct f2fs_sb_info *sbi) > >>> { > >>> struct f2fs_sm_info *sm_info = SM_I(sbi); > >>> + if (!sm_info) > >>> + return; > >>> destroy_dirty_segmap(sbi); > >>> destroy_curseg(sbi); > >>> destroy_free_segmap(sbi); > > > > > > > > > =