Re: [PATCH v2] xfstests/xfs: xfs_repair secondary sb verification regression test

["gux.fnst" <gux.fnst@cn.fujitsu.com>]

Hi,

This test case always fail like this:
xfs/070	 - output mismatch (see /var/lib/xfstests/results//xfs/070.out.bad)
     --- tests/xfs/070.out	2015-03-17 14:30:45.671000000 +0800
     +++ /var/lib/xfstests/results//xfs/070.out.bad	2015-03-30 13:33:44.450000000 +0800
     @@ -7,6 +7,7 @@
      bad on-disk superblock AGNO - bad magic number
      primary/secondary superblock AGNO conflict - AG superblock geometry info conflicts with filesystem geometry
      zeroing unused portion of secondary superblock (AG #AGNO)
     +non-null project quota inode field in superblock AGNO
      reset bad sb for ag AGNO
              - found root inode chunk
      Phase 3 - for each AG...
     ...
     (Run 'diff -u tests/xfs/070.out /var/lib/xfstests/results//xfs/070.out.bad'  to see the entire diff)
Is this failure caused by message loss in the golden output? Thanks!

Regards,
Xing Gu

On 01/21/2015 11:37 PM, Brian Foster wrote:
> The secondary superblock verification in xfs_repair was subject to a bug
> that unnecessarily leads to a brute force superblock scan if the last
> superblock in the fs happens to be corrupt. Normally, xfs_repair handles
> one-off superblock corruption gracefully using a heuristic that finds
> the most consistent superblock content across the set of secondary
> superblocks.
>
> Create a regression test for xfs_repair that corrupts the last
> superblock in the fs. Verify the superblock is updated from the
> previously verified sb content and a brute force scan is not initiated.
> In the event of failure, detect that a brute force scan has started and
> abort the repair in order to fail the test quickly.
>
> To support the test, extend the xfs_repair filter to handle corrupted
> superblock repair output and provide generic test output for arbitrary
> AG counts.
>
> Signed-off-by: Brian Foster <bfoster@redhat.com>
> ---
>
> v2:
> - Use pgrep instead of ps to monitor xfs_repair process.
> - Use mkfs filter instead of xfs_db to obtain agcount of scratch fs.
> v1: http://oss.sgi.com/archives/xfs/2015-01/msg00321.html
>
>   common/repair     |   4 ++
>   tests/xfs/069     | 110 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>   tests/xfs/069.out |  27 ++++++++++++++
>   tests/xfs/group   |   1 +
>   4 files changed, 142 insertions(+)
>   create mode 100755 tests/xfs/069
>   create mode 100644 tests/xfs/069.out
>
> diff --git a/common/repair b/common/repair
> index a157580..7a99546 100644
> --- a/common/repair
> +++ b/common/repair
> @@ -88,6 +88,10 @@ s/(inode chunk) (\d+)\/(\d+)/AGNO\/INO/;
>   # sunit/swidth reset messages
>   s/^(Note - .*) were copied.*/\1 fields have been reset./;
>   s/^(Please) reset (with .*) if necessary/\1 set \2/;
> +# corrupt sb messages
> +s/(superblock) (\d+)/\1 AGNO/;
> +s/(AG \#)(\d+)/\1AGNO/;
> +s/(reset bad sb for ag) (\d+)/\1 AGNO/;
>   	print;'
>   }
>
> diff --git a/tests/xfs/069 b/tests/xfs/069
> new file mode 100755
> index 0000000..1432761
> --- /dev/null
> +++ b/tests/xfs/069
> @@ -0,0 +1,110 @@
> +#! /bin/bash
> +# FS QA Test No. 069
> +#
> +# As part of superblock verification, xfs_repair checks the primary sb and
> +# verifies all secondary sb's against the primary. In the event of geometry
> +# inconsistency, repair uses a heuristic that tracks the most frequently
> +# occurring settings across the set of N (agcount) superblocks.
> +#
> +# xfs_repair was subject to a bug that disregards this heuristic in the event
> +# that the last secondary superblock in the fs is corrupt. The side effect is an
> +# unnecessary and potentially time consuming brute force superblock scan.
> +#
> +# This is a regression test for the aforementioned xfs_repair bug. We
> +# intentionally corrupt the last superblock in the fs, run xfs_repair and
> +# verify it repairs the fs correctly. We explicitly detect a brute force scan
> +# and abort the repair to save time in the failure case.
> +#
> +#-----------------------------------------------------------------------
> +# Copyright (c) 2015 Red Hat, Inc. All Rights Reserved.
> +#
> +# This program is free software; you can redistribute it and/or
> +# modify it under the terms of the GNU General Public License as
> +# published by the Free Software Foundation.
> +#
> +# This program is distributed in the hope that it would be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program; if not, write the Free Software Foundation,
> +# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
> +#-----------------------------------------------------------------------
> +#
> +
> +seq=`basename $0`
> +seqres=$RESULT_DIR/$seq
> +echo "QA output created by $seq"
> +
> +here=`pwd`
> +tmp=/tmp/$$
> +status=1	# failure is the default!
> +trap "_cleanup; exit \$status" 0 1 2 3 15
> +
> +_cleanup()
> +{
> +	cd /
> +	rm -f $tmp.*
> +	killall -9 $XFS_REPAIR_PROG > /dev/null 2>&1
> +	wait > /dev/null 2>&1
> +}
> +
> +# Start and monitor an xfs_repair of the scratch device. This test can induce a
> +# time consuming brute force superblock scan. Since a brute force scan means
> +# test failure, detect it and end the repair.
> +_xfs_repair_noscan()
> +{
> +	# invoke repair directly so we can kill the process if need be
> +	$XFS_REPAIR_PROG $SCRATCH_DEV 2>&1 | tee -a $seqres.full > $tmp.repair &
> +	repair_pid=$!
> +
> +	# monitor progress for as long as it is running
> +	while [ `pgrep xfs_repair` ]; do
> +		grep "couldn't verify primary superblock" $tmp.repair \
> +			> /dev/null 2>&1
> +		if [ $? == 0 ]; then
> +			# we've started a brute force scan. kill repair and
> +			# fail the test
> +			kill -9 $repair_pid >> $seqres.full 2>&1
> +			wait >> $seqres.full 2>&1
> +
> +			_fail "xfs_repair resorted to brute force scan"
> +		fi
> +
> +		sleep 1
> +	done
> +
> +	wait
> +
> +	cat $tmp.repair | _filter_repair
> +}
> +
> +rm -f $seqres.full
> +
> +# get standard environment, filters and checks
> +. ./common/rc
> +. ./common/filter
> +. ./common/repair
> +
> +# real QA test starts here
> +
> +# Modify as appropriate.
> +_supported_fs xfs
> +_supported_os Linux
> +_require_scratch_nocheck
> +
> +_scratch_mkfs | _filter_mkfs > /dev/null 2> $tmp.mkfs || _fail "mkfs failed"
> +
> +. $tmp.mkfs # import agcount
> +
> +# corrupt the last secondary sb in the fs
> +$XFS_DB_PROG -x -c "sb $((agcount - 1))" -c "type data" \
> +	-c "write fill 0xff 0 512" $SCRATCH_DEV
> +
> +# attempt to repair
> +_xfs_repair_noscan
> +
> +# success, all done
> +status=0
> +exit
> diff --git a/tests/xfs/069.out b/tests/xfs/069.out
> new file mode 100644
> index 0000000..c6b11d1
> --- /dev/null
> +++ b/tests/xfs/069.out
> @@ -0,0 +1,27 @@
> +QA output created by 069
> +Phase 1 - find and verify superblock...
> +Phase 2 - using <TYPEOF> log
> +        - zero log...
> +        - scan filesystem freespace and inode maps...
> +bad magic number
> +bad on-disk superblock AGNO - bad magic number
> +primary/secondary superblock AGNO conflict - AG superblock geometry info conflicts with filesystem geometry
> +zeroing unused portion of secondary superblock (AG #AGNO)
> +reset bad sb for ag AGNO
> +        - found root inode chunk
> +Phase 3 - for each AG...
> +        - scan and clear agi unlinked lists...
> +        - process known inodes and perform inode discovery...
> +        - process newly discovered inodes...
> +Phase 4 - check for duplicate blocks...
> +        - setting up duplicate extent list...
> +        - check for inodes claiming duplicate blocks...
> +Phase 5 - rebuild AG headers and trees...
> +        - reset superblock...
> +Phase 6 - check inode connectivity...
> +        - resetting contents of realtime bitmap and summary inodes
> +        - traversing filesystem ...
> +        - traversal finished ...
> +        - moving disconnected inodes to lost+found ...
> +Phase 7 - verify and correct link counts...
> +done
> diff --git a/tests/xfs/group b/tests/xfs/group
> index 496630d..9394703 100644
> --- a/tests/xfs/group
> +++ b/tests/xfs/group
> @@ -66,6 +66,7 @@
>   066 dump ioctl auto quick
>   067 acl attr auto quick
>   068 auto stress dump
> +069 auto quick repair
>   071 rw auto
>   072 rw auto prealloc quick
>   073 copy auto
>