From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from p3nlsmtpcp01-01.prod.phx3.secureserver.net ([184.168.200.138]:35328 "EHLO p3nlsmtpcp01-01.prod.phx3.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750806AbdBOJPc (ORCPT ); Wed, 15 Feb 2017 04:15:32 -0500 Date: Wed, 15 Feb 2017 14:44:05 +0530 From: "Lakshmipathi.G" To: Qu Wenruo , linux-btrfs@vger.kernel.org Subject: Re: [PATCH] btrfs-progs: misc-tests: Primary Superblock corruption and recovery using backup Superblock. Message-ID: <20170215091405.GA11896@giis.co.in> References: <20170214213125.GA25514@giis.co.in> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Wed, Feb 15, 2017 at 09:36:03AM +0800, Qu Wenruo wrote: > > > >+ # Corrupt superblock checksum > >+ dd if=/dev/zero of=$TEST_DEV seek=$superblock_offset bs=1 \ > >+ count=4 conv=notrunc &> /dev/null > >+ run_check_stdout $SUDO_HELPER mount $TEST_DEV $TEST_MNT | \ > >+ grep -q 'wrong fs type' > > What about using btrfs check instead of trying to mount it? > > This could emit the need to use $SUDO_HELPER, and could catch super error > more accurate. > > >+ if [ $? -ne 0 ]; then > >+ _fail "Failed to corrupt superblock." > >+ fi > >+ > >+ # Copy backup superblock to primary > >+ run_check $TOP/btrfs-select-super -s 1 $TEST_DEV > >+ run_check $SUDO_HELPER mount $TEST_DEV $TEST_MNT > Same here. I started with 'btrfs check' and 'btrfs check --repair' but it seems like --repair don't fix the corruption. So just moved away from using it. After you mentioned, now I see 'btrfs check' will be helpful. Will make these changes. Cheers. Lakshmipathi.G