From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp205.alice.it ([82.57.200.101]:57758 "EHLO smtp205.alice.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752528Ab2IDSOS (ORCPT ); Tue, 4 Sep 2012 14:14:18 -0400 Message-ID: <5046452C.7090804@libero.it> Date: Tue, 04 Sep 2012 20:15:08 +0200 From: Goffredo Baroncelli Reply-To: kreijack@inwind.it MIME-Version: 1.0 To: Shentino CC: Michael , cwillu , linux-btrfs@vger.kernel.org Subject: Re: rfc: fuzz testing by direct writes to device References: In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi, On 09/02/2012 03:03 AM, Shentino wrote: > This whole subject was also about using sed to corrupt-o-magic a > file's data on disk. > > Is this an acceptable method for testing? I am not sure that doing "sed /dev/sdX ..." is the right thing to do, because it rewrites the full disk. This means that: - it takes a lot of time - you don't have any control about which part of the disk you change: what happens if sed write a block which is update in parallel by BTRFS ? Anyway I suggest to give a look to the following video [1], which explains the automatic repair. Moreover it shows [2] how corrupt a block with the "btrfs-corrupt-block" command. Hoping that this helps you. BR G.Baroncelli [1] http://www.youtube.com/watch?v=hxWuaozpe2I [2] See minute 17:52 of the video above > > On Sat, Sep 1, 2012 at 4:49 PM, Michael wrote: >> It should not. It is always preferred that you dd your drive onto >> another disk just in case though. >> >> On Sat, Sep 1, 2012 at 5:31 PM, Shentino wrote: >>> On Sat, Sep 1, 2012 at 1:59 PM, cwillu wrote: >>>> You still haven't said which kernel you were running; the thing to do >>>> is try the very latest rc (if not btrfs-next). >>> >>> Sorry about that! >>> >>> I thought I included it. >>> >>> 3.3.8 >>> >>> Hmm...seems it's been EOL'ed. I need to yell at my distro. >>> >>> In the meantime, will mounting a btrfs filesystem with a new kernel >>> render it unmountable by older kernels? > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > . >