From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from userp2120.oracle.com ([156.151.31.85]:46358 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390723AbfITEbf (ORCPT ); Fri, 20 Sep 2019 00:31:35 -0400 Date: Thu, 19 Sep 2019 21:29:22 -0700 From: "Darrick J. Wong" Subject: Re: [PATCH] common/xfs: wipe the XFS superblock of each AGs Message-ID: <20190920042922.GQ2229799@magnolia> References: <20190919150024.8346-1-zlang@redhat.com> <66503981-2ff3-f28b-fd06-9d6360c930fe@cn.fujitsu.com> <20190920024836.GO2229799@magnolia> <20190920043139.GO7239@dhcp-12-102.nay.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190920043139.GO7239@dhcp-12-102.nay.redhat.com> Sender: fstests-owner@vger.kernel.org To: Zorro Lang Cc: fstests@vger.kernel.org, linux-xfs@vger.kernel.org List-ID: On Fri, Sep 20, 2019 at 12:31:39PM +0800, Zorro Lang wrote: > On Thu, Sep 19, 2019 at 07:48:36PM -0700, Darrick J. Wong wrote: > > On Fri, Sep 20, 2019 at 09:52:11AM +0800, Yang Xu wrote: > > > > > > > > > on 2019/09/19 23:00, Zorro Lang wrote: > > > > xfs/030 always fails after d0e484ac699f ("check: wipe scratch devices > > > > between tests") get merged. > > > > > > > > Due to xfs/030 does a sized(100m) mkfs. Before we merge above commit, > > > > mkfs.xfs detects an old primary superblock, it will write zeroes to > > > > all superblocks before formatting the new filesystem. But this won't > > > > be done if we wipe the first superblock(by merging above commit). > > > > > > > > That means if we make a (smaller) sized xfs after wipefs, those *old* > > > > superblocks which created by last time mkfs.xfs will be left on disk. > > > > Then when we do xfs_repair, if xfs_repair can't find the first SB, it > > > > will go to find those *old* SB at first. When it finds them, > > > > everyting goes wrong. > > > > > > > > So I try to get XFS AG geometry(by default) and then try to erase all > > > > superblocks. Thanks Darrick J. Wong helped to analyze this issue. > > > Feel free to add Reported-by. > > > > > > > > Signed-off-by: Zorro Lang > > > > --- > > > > common/rc | 4 ++++ > > > > common/xfs | 23 +++++++++++++++++++++++ > > > > 2 files changed, 27 insertions(+) > > > > > > > > diff --git a/common/rc b/common/rc > > > > index 66c7fd4d..fe13f659 100644 > > > > --- a/common/rc > > > > +++ b/common/rc > > > > @@ -4048,6 +4048,10 @@ _try_wipe_scratch_devs() > > > > for dev in $SCRATCH_DEV_POOL $SCRATCH_DEV $SCRATCH_LOGDEV $SCRATCH_RTDEV; do > > > > test -b $dev && $WIPEFS_PROG -a $dev > > > > done > > > > + > > > > + if [ "$FSTYP" = "xfs" ];then > > > > + try_wipe_scratch_xfs > > > I think we should add a simple comment for why we add it. > > > > > > ps:_scratch_mkfs_xfs also can make case pass. We can use it and add comment. > > > the try_wipe_scratch_xfs method and the _scratch_mkfs_xfs method are all > > > acceptable for me. > > > > Yes, I suppose formatting and then wiping per below would also achieve > > our means, but it would come at the extra cost of zeroing the log. I'm > > not too eager to increase xfstest runtime even more. > > > > Hmmm, I wonder if xfs_db could just grow a 'wipe all superblocks' > > command.... > > Haha, I was thinking about that too, and I tried this: > -- > agc=`_scratch_xfs_get_sb_field agcount` > wipe_xfs_cmd="$XFS_DB_PROG -x" > for ((i=0; i wipe_xfs_cmd="$wipe_xfs_cmd -c \"sb $i\" -c \"write -c magicnum 0x00000000\"" > done > wipe_xfs_cmd="$wipe_xfs_cmd $SCRATCH_DEV" > eval $wipe_xfs_cmd > -- > > The only one problem about this, I think it's the max length of bash command:) Yeah... I mean, the downside of all this is that a filesystme could have thousands of AGs, though I don't imagine there are many people who set up a 1PB array just to run xfstests ;) --D > Thanks, > Zorro > > > > > --D > > > > > > + fi > > > > } > > > > # Only run this on xfs if xfs_scrub is available and has the unicode checker > > > > diff --git a/common/xfs b/common/xfs > > > > index 1bce3c18..34516f82 100644 > > > > --- a/common/xfs > > > > +++ b/common/xfs > > > > @@ -884,3 +884,26 @@ _xfs_mount_agcount() > > > > { > > > > $XFS_INFO_PROG "$1" | grep agcount= | sed -e 's/^.*agcount=\([0-9]*\),.*$/\1/g' > > > > } > > > > + > > > > +# wipe the superblock of each XFS AGs > > > > +try_wipe_scratch_xfs() > > > > +{ > > > > + local tmp=`mktemp -u` > > > > + > > > > + _scratch_mkfs_xfs -N 2>/dev/null | perl -ne ' > > > > + if (/^meta-data=.*\s+agcount=(\d+), agsize=(\d+) blks/) { > > > > + print STDOUT "agcount=$1\nagsize=$2\n"; > > > > + } > > > > + if (/^data\s+=\s+bsize=(\d+)\s/) { > > > > + print STDOUT "dbsize=$1\n"; > > > > + }' > $tmp.mkfs > > > > + > > > > + . $tmp.mkfs > > > > + if [ -n "$agcount" -a -n "$agsize" -a -n "$dbsize" ];then > > > > + for ((i = 0; i < agcount; i++)); do > > > > + $XFS_IO_PROG -c "pwrite $((i * dbsize * agsize)) $dbsize" \ > > > > + $SCRATCH_DEV >/dev/null; > > > > + done > > > > + fi > > > > + rm -f $tmp.mkfs > > > > +} > > > > > > > > > >