From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:42304 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751795AbdIVTcR (ORCPT ); Fri, 22 Sep 2017 15:32:17 -0400 Date: Fri, 22 Sep 2017 12:28:30 -0700 From: Liu Bo To: Lu Fengqi Cc: fstests@vger.kernel.org, linux-btrfs@vger.kernel.org Subject: Re: [PATCH] fstests: btrfs/150 regression test for reading compressed data Message-ID: <20170922192829.GB8109@lim.localdomain> Reply-To: bo.li.liu@oracle.com References: <20170920235243.11822-1-bo.li.liu@oracle.com> <20170921070344.GB471@fnst.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20170921070344.GB471@fnst.localdomain> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Thu, Sep 21, 2017 at 03:03:45PM +0800, Lu Fengqi wrote: > On Wed, Sep 20, 2017 at 05:52:43PM -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 > >--- > > tests/btrfs/150 | 102 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > > tests/btrfs/150.out | 3 ++ > > tests/btrfs/group | 1 + > > 3 files changed, 106 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..834be51 > >--- /dev/null > >+++ b/tests/btrfs/150 > >@@ -0,0 +1,102 @@ > >+#! /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 for this is > >+# xxxxx > >+# > >+#----------------------------------------------------------------------- > >+# Copyright (c) 2017 Liu Bo. 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 > >+ > >+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 > > What does 1000 mean? Enough failures? > Why not set times to -1? This was copied from another test, so I kept it as is. As this test just submits a single 8K read after enabling fault injection, 1000 is in fact as same as -1(no limit), I think 1000 is OK to use. thanks, -liubo > > >+ 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 true; do > >+ disable_io_failure > >+ # invalidate the page cache > >+ $XFS_IO_PROG -f -c "fadvise -d 0 128K" $SCRATCH_MNT/foobar | _filter_xfs_io > >+ > >+ enable_io_failure > >+ od -x $SCRATCH_MNT/foobar > /dev/null & > >+ pid=$! > >+ wait > >+ [ $((pid % 2)) == 1 ] && break > >+done > >+ > >+disable_io_failure > >+ > >+# 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..b70a122 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 > >-- > >2.5.0 > > > >-- > >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 > > > > > > -- > Thanks, > Lu > >