When one process opens a loop device partition and another process detaches
it, there will be a race condition due to which stale loop partitions are
created causing IO errors. This test will detect the race.
Signed-off-by: Gulam Mohamed <gulam.mohamed@xxxxxxxxxx>
---
v4<-v3:
1. Resolved formatting issues
2. Using long options for commands instead of short options
tests/loop/010 | 75 ++++++++++++++++++++++++++++++++++++++++++++++
tests/loop/010.out | 2 ++
2 files changed, 77 insertions(+)
create mode 100755 tests/loop/010
create mode 100644 tests/loop/010.out
diff --git a/tests/loop/010 b/tests/loop/010
new file mode 100755
index 000000000000..f5d1bf1f9c18
--- /dev/null
+++ b/tests/loop/010
@@ -0,0 +1,75 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-3.0+
+# Copyright (C) 2024, Oracle and/or its affiliates.
+#
+# Test to detect a race between loop detach and loop open which creates
+# stale loop partitions when one process opens the loop partition and
+# another process detaches the loop device.
+#
+. tests/loop/rc
+DESCRIPTION="check stale loop partition"
+TIMED=1
+
+requires() {
+ _have_program parted
+ _have_program mkfs.xfs
+}
+
+image_file="$TMPDIR/loopImg"
+
+create_loop() {
+ while true
+ do
+ loop_device="$(losetup --partscan --find --show "${image_file}")"
+ blkid /dev/loop0p1 >& /dev/null
+ done
+}
+
+detach_loop() {
+ while true
+ do
+ if [ -e /dev/loop0 ]; then
+ losetup --detach /dev/loop0 >& /dev/null
+ fi
+ done
+}
+
+test() {
+ echo "Running ${TEST_NAME}"
+ local loop_device
+ local create_pid
+ local detach_pid
+
+ truncate --size 1G "${image_file}"
+ parted --align none --script "${image_file}" mklabel gpt
+ loop_device="$(losetup --partscan --find --show "${image_file}")"
+ parted --align none --script "${loop_device}" mkpart primary 64s 109051s
+
+ udevadm settle
+
+ if [ ! -e "${loop_device}" ]; then
+ return 1
+ fi
+
+ mkfs.xfs --force "${loop_device}p1" >& /dev/null
+ losetup --detach "${loop_device}" >& /dev/null
+
+ create_loop &
+ create_pid=$!
+ detach_loop &
+ detach_pid=$!
+
+ sleep "${TIMEOUT:-90}"
+ {
+ kill -9 $create_pid
+ kill -9 $detach_pid
+ wait
+ sleep 1
+ } 2>/dev/null
+
+ losetup --detach-all >& /dev/null
+ if _dmesg_since_test_start | grep --quiet "partition scan of loop0 failed (rc=-16)"; then
+ echo "Fail"
+ fi
+ echo "Test complete"
+}
diff --git a/tests/loop/010.out b/tests/loop/010.out
new file mode 100644
index 000000000000..64a6aee00b8a
--- /dev/null
+++ b/tests/loop/010.out
@@ -0,0 +1,2 @@
+Running loop/010
+Test complete
--
2.39.3
