From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752938Ab0CUK34 (ORCPT ); Sun, 21 Mar 2010 06:29:56 -0400 Received: from mail-gy0-f174.google.com ([209.85.160.174]:61206 "EHLO mail-gy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752687Ab0CUK3y convert rfc822-to-8bit (ORCPT ); Sun, 21 Mar 2010 06:29:54 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=iUBj8UotUMAy93DM0vnsGLxLWhg9kPO/TPD10uR2Jm8u7TMPzwG9MzY8jT6Qzq56A8 t+vmiOyQZd1JR6Ww1ZggP0um/hgAv5qFyKjAfGVeeCTy0wpgxWgcSVKwbbnQPN7ouRYi syjcJLDN7sTJ05jjvTPCeU4AlAzZD7r5ERDQE= MIME-Version: 1.0 In-Reply-To: <4BA3C461.5060209@gmx.net> References: <4BA3C07A.8030204@gmx.net> <73e903671003191123h1b7e1196v336265842f1b29e5@mail.gmail.com> <4BA3C461.5060209@gmx.net> Date: Sun, 21 Mar 2010 18:29:53 +0800 Message-ID: Subject: Re: BUG:write data to degrade raid5 From: jin zhencheng To: Joachim Otahal Cc: =?ISO-8859-1?Q?Kristleifur_Da=F0ason?= , neilb@suse.de, linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-9 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org hi Joachim Otahal: ths for your test on "Debian 2.6.26-21lenny4". if you want to see the oop ,you should always write to the raid5 ,and pull 2 disks out.maybe you can see the error i think no matter what i do ,even if i pull out all the disk , kernel should not oop. On Sat, Mar 20, 2010 at 2:37 AM, Joachim Otahal wrote: > Kristleifur Dađason schrieb: >> >> On Fri, Mar 19, 2010 at 6:20 PM, Joachim Otahal > > wrote: >> >>    jin zhencheng schrieb: >> >>        hi; >> >>        i use kernel is 2.6.26.2 >> >>        what i do as follow: >> >>        1, I create a raid5: >>        mdadm -C /dev/md5 -l 5 -n 4 /dev/sda /dev/sdb /dev/sdc  /dev/sdd >>        --metadata=1.0 --assume-clean >> >>        2, dd if=/dev/zero of=/dev/md5 bs=1M& >> >>        write data to this raid5 >> >>        3, mdadm --manage /dev/md5 -f /dev/sda >> >>        4 mdadm --manage  /dev/md5 -f /dev/sdb >> >>        if i faild 2 disks ,then the OS kernel display OOP error and >>        kernel down >> >>        do somebody know why ? >> >>        Is MD/RAID5 bug ? >> >> >>    RAID5 can only tolerate ONE drive to fail of ALL members. If you >>    want to be able to fail two drives you will have to use RAID6 or >>    RAID5 with one hot-spare (and give it time to rebuild before >>    failing the second drive). >>    PLEASE read the documentation on raid levels, like on wikipedia. >> >> >> That is true, >> >> but should we get a kernel oops and crash if two RAID5 drives are failed? >> (THAT part looks like a bug!) >> >> Jin, can you try a newer kernel, and a newer mdadm? >> >> -- Kristleifur > > You are probably right. > My kernel version is "Debian 2.6.26-21lenny4", and I had no oopses during my > hot-plug testing one the hardware I use md on. I think it may be the driver > for his chips. > > Jin: > > Did you really use the whole drives for testing or loopback files or > partitions on the drives? I never did my hot-plug testings with whole drives > being in an array, only with partitions. > > Joachim Otahal > >