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+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2020 SUSE Linux Products GmbH. All Rights Reserved.
+#
+# FS QA Test 213
+#
+# Test if canceling a running balance can lead to dead looping balance
+#
+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 $seqres.full
+
+# Modify as appropriate.
+_supported_fs btrfs
+_supported_os Linux
+_require_scratch
+_require_command "$KILLALL_PROG" killall
+
+_scratch_mkfs >> $seqres.full
+_scratch_mount
+
+runtime=4
+
+# Create enough IO so that we need around $runtime seconds to relocate it
+dd if=/dev/zero bs=1M of="$SCRATCH_MNT/file" oflag=sync status=none \
+ &> /dev/null &
+dd_pid=$!
+sleep $runtime
+"$KILLALL_PROG" -q dd &> /dev/null
+wait $dd_pid
+
+ps aux >> $seqres.full
+# Now balance should take at least $runtime seconds, we can cancel it at
+# $runtime/2 to ensure a success cancel.
+$BTRFS_UTIL_PROG balance start -d --bg "$SCRATCH_MNT"
+sleep $(($runtime / 2))
+$BTRFS_UTIL_PROG balance cancel "$SCRATCH_MNT"
+
+# Now check if we can finish relocating metadata, which should finish very
+# quickly
+$BTRFS_UTIL_PROG balance start -m "$SCRATCH_MNT" >> $seqres.full
+
+lsof > /tmp/lsof
+echo "Silence is golden"
+
+# success, all done
+status=0
+exit
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+QA output created by 213
+Silence is golden
@@ -215,3 +215,4 @@
210 auto quick qgroup snapshot
211 auto quick log prealloc
212 auto balance dangerous
+213 auto fast balance dangerous
Test if canceling a running balance can cause later balance to dead loop. The ifx is titled "btrfs: relocation: Clear the DEAD_RELOC_TREE bit for orphan roots to prevent runaway balance". Signed-off-by: Qu Wenruo <wqu@suse.com> --- tests/btrfs/213 | 66 +++++++++++++++++++++++++++++++++++++++++++++ tests/btrfs/213.out | 2 ++ tests/btrfs/group | 1 + 3 files changed, 69 insertions(+) create mode 100755 tests/btrfs/213 create mode 100644 tests/btrfs/213.out