From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:44158 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967311AbdIZJCi (ORCPT ); Tue, 26 Sep 2017 05:02:38 -0400 Date: Tue, 26 Sep 2017 17:02:36 +0800 From: Eryu Guan To: Liu Bo Cc: fstests@vger.kernel.org, linux-btrfs@vger.kernel.org Subject: Re: [PATCH v2] fstests: btrfs/150 regression test for reading compressed data Message-ID: <20170926090236.GI8034@eguan.usersys.redhat.com> References: <20170920235243.11822-1-bo.li.liu@oracle.com> <20170922232127.12032-1-bo.li.liu@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20170922232127.12032-1-bo.li.liu@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Fri, Sep 22, 2017 at 05:21:27PM -0600, Liu Bo wrote: > We had a bug in btrfs compression code which could end up with a > kernel panic. > > This is adding a regression test for the bug and I've also sent a > kernel patch to fix the bug. > > The patch is "Btrfs: fix kernel oops while reading compressed data". > > Signed-off-by: Liu Bo Hmm, I can't reproduce the panic with 4.13 kernel, which doesn't have the fix applied. Can you please help confirm if it panics on your test environment? > --- > v2: - Fix ambiguous copyright. > - Use /proc/$pid/make-it-fail to specify IO failure > - Use bash -c to run test only when pid is odd. > - Add test to dangerous group. > > tests/btrfs/150 | 103 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > tests/btrfs/150.out | 3 ++ > tests/btrfs/group | 1 + > 3 files changed, 107 insertions(+) > create mode 100755 tests/btrfs/150 > create mode 100644 tests/btrfs/150.out > > diff --git a/tests/btrfs/150 b/tests/btrfs/150 > new file mode 100755 > index 0000000..8891c38 > --- /dev/null > +++ b/tests/btrfs/150 > @@ -0,0 +1,103 @@ > +#! /bin/bash > +# FS QA Test btrfs/150 > +# > +# This is a regression test which ends up with a kernel oops in btrfs. > +# It occurs when btrfs's read repair happens while reading a compressed > +# extent. > +# The patch to fix it is > +# Btrfs: fix kernel oops while reading compressed data > +# > +#----------------------------------------------------------------------- > +# Copyright (c) 2017 Oracle. 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.* > +} > + > +# get standard environment, filters and checks > +. ./common/rc > +. ./common/filter > + > +# remove previous $seqres.full before test > +rm -f $seqres.full > + > +# real QA test starts here > + > +# Modify as appropriate. > +_supported_fs btrfs > +_supported_os Linux > +_require_scratch > +_require_fail_make_request > +_require_scratch_dev_pool 2 Trailing whitespace in above line. > + > +SYSFS_BDEV=`_sysfs_dev $SCRATCH_DEV` > +enable_io_failure() > +{ > + echo 100 > $DEBUGFS_MNT/fail_make_request/probability > + echo 1000 > $DEBUGFS_MNT/fail_make_request/times > + echo 0 > $DEBUGFS_MNT/fail_make_request/verbose > + echo 1 > $SYSFS_BDEV/make-it-fail > +} > + > +disable_io_failure() > +{ > + echo 0 > $SYSFS_BDEV/make-it-fail > + echo 0 > $DEBUGFS_MNT/fail_make_request/probability > + echo 0 > $DEBUGFS_MNT/fail_make_request/times > +} > + > +_scratch_pool_mkfs "-d raid1 -b 1G" >> $seqres.full 2>&1 > + > +# It doesn't matter which compression algorithm we use. > +_scratch_mount -ocompress > + > +# Create a file with all data being compressed > +$XFS_IO_PROG -f -c "pwrite -W 0 8K" $SCRATCH_MNT/foobar | _filter_xfs_io > + > +# Raid1 consists of two copies and btrfs decides which copy to read by reader's > +# %pid. Now we inject errors to copy #1 and copy #0 is good. We want to read > +# the bad copy to trigger read-repair. > +while [[ -z $result ]]; do > + # invalidate the page cache > + $XFS_IO_PROG -f -c "fadvise -d 0 8K" $SCRATCH_MNT/foobar Does 'echo 3 > /proc/sys/vm/drop_caches' work? Thanks, Eryu > + > + enable_io_failure > + > + result=$(bash -c " > + if [ \$((\$\$ % 2)) == 1 ]; then > + echo 1 > /proc/\$\$/make-it-fail > + exec $XFS_IO_PROG -c \"pread 0 8K\" \$SCRATCH_MNT/foobar > + fi") > + > + disable_io_failure > +done > + > +# success, all done > +status=0 > +exit > diff --git a/tests/btrfs/150.out b/tests/btrfs/150.out > new file mode 100644 > index 0000000..c492c24 > --- /dev/null > +++ b/tests/btrfs/150.out > @@ -0,0 +1,3 @@ > +QA output created by 150 > +wrote 8192/8192 bytes at offset 0 > +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) > diff --git a/tests/btrfs/group b/tests/btrfs/group > index 70c3f05..e73bb1b 100644 > --- a/tests/btrfs/group > +++ b/tests/btrfs/group > @@ -152,3 +152,4 @@ > 147 auto quick send > 148 auto quick rw > 149 auto quick send compress > +150 auto quick dangerous > -- > 2.5.0 > > -- > To unsubscribe from this list: send the line "unsubscribe fstests" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html