From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964917AbWFTEh3 (ORCPT ); Tue, 20 Jun 2006 00:37:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964918AbWFTEh3 (ORCPT ); Tue, 20 Jun 2006 00:37:29 -0400 Received: from mf2.realtek.com.tw ([60.248.182.46]:21769 "EHLO mf2.realtek.com.tw") by vger.kernel.org with ESMTP id S964917AbWFTEh2 (ORCPT ); Tue, 20 Jun 2006 00:37:28 -0400 Message-ID: <004301c69423$365d53d0$106215ac@realtek.com.tw> From: "colin" To: "Alan Cox" Cc: References: <045101c69108$4992a130$106215ac@realtek.com.tw> <1150709551.2503.6.camel@localhost.localdomain> Subject: Re: UDF filesystem has some bugs on truncating Date: Tue, 20 Jun 2006 12:37:18 +0800 MIME-Version: 1.0 X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1807 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1807 X-MIMETrack: Itemize by SMTP Server on msx/Realtek(Release 6.5.3|September 14, 2004) at 2006/06/20 =?Bog5?B?pFWkyCAxMjozNzoxOA==?=, Serialize by Router on msx/Realtek(Release 6.5.3|September 14, 2004) at 2006/06/20 =?Bog5?B?pFWkyCAxMjozNzoyMQ==?=, Serialize complete at 2006/06/20 =?Bog5?B?pFWkyCAxMjozNzoyMQ==?= Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="big5" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi Alan, Do you use the same command with me? The parameter "seek" of "dd if=/dev/zero of=aaa bs=1024k count=2 seek=3000" will inform "dd" to use truncate system call to expand file in no time. In normal situations, the file will grow up to 3G in about 2 seconds. This dd command on ext3 partition can run very well on my platform, but it will fail on UDF partition. Regards, Colin ----- Original Message ----- From: "Alan Cox" To: "colin" Cc: Sent: Monday, June 19, 2006 5:32 PM Subject: Re: UDF filesystem has some bugs on truncating > Ar Gwe, 2006-06-16 am 13:47 +0800, ysgrifennodd colin: > > Hi all, > > I found that UDF has bugs on truncating. > > When you do this: > > dd if=/dev/zero of=aaa bs=1024k count=2 seek=3000 > > , Linux will hang and die. > > The platform is Linux 2.6.16 on MIPS malta board. > > Ok I eventually sort of reproduced this on x86-64. It took a while > because in my environment I see a crash 2 or 3 hours after the test is > run, and that crash is on hardware that doesn't otherwise crash and > seems to be repeatable. > > Alan >