diff --git a/tests/qemu-iotests/240 b/tests/qemu-iotests/240
index 8b4337b58d..a739de6769 100755
--- a/tests/qemu-iotests/240
+++ b/tests/qemu-iotests/240
@@ -1,5 +1,5 @@
-#!/usr/bin/env bash
-#
+#!/usr/bin/env python3
+
 # Test hot plugging and unplugging with iothreads
 #
 # Copyright (C) 2019 Igalia, S.L.
@@ -17,133 +17,99 @@
 #
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
-#
 
-# creator
-owner=berto@igalia.com
-
-seq=`basename $0`
-echo "QA output created by $seq"
-
-status=1	# failure is the default!
-
-_cleanup()
-{
-    rm -f "$SOCK_DIR/nbd"
-}
-trap "_cleanup; exit \$status" 0 1 2 3 15
-
-# get standard environment, filters and checks
-. ./common.rc
-. ./common.filter
-
-_supported_fmt generic
-_supported_proto generic
-
-do_run_qemu()
-{
-    echo Testing: "$@"
-    $QEMU -nographic -qmp stdio -serial none "$@"
-    echo
-}
-
-# Remove QMP events from (pretty-printed) output. Doesn't handle
-# nested dicts correctly, but we don't get any of those in this test.
-_filter_qmp_events()
-{
-    tr '\n' '\t' | sed -e \
-	's/{\s*"timestamp":\s*{[^}]*},\s*"event":[^,}]*\(,\s*"data":\s*{[^}]*}\)\?\s*}\s*//g' \
-	| tr '\t' '\n'
-}
-
-run_qemu()
-{
-    do_run_qemu "$@" 2>&1 | _filter_qmp | _filter_qmp_events
-}
-
-case "$QEMU_DEFAULT_MACHINE" in
-  s390-ccw-virtio)
-      virtio_scsi=virtio-scsi-ccw
-      ;;
-  *)
-      virtio_scsi=virtio-scsi-pci
-      ;;
-esac
-
-echo
-echo === Unplug a SCSI disk and then plug it again ===
-echo
-
-run_qemu <<EOF
-{ "execute": "qmp_capabilities" }
-{ "execute": "blockdev-add", "arguments": {"driver": "null-co", "read-zeroes": true, "node-name": "hd0"}}
-{ "execute": "object-add", "arguments": {"qom-type": "iothread", "id": "iothread0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi0", "driver": "${virtio_scsi}", "iothread": "iothread0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi-hd0", "driver": "scsi-hd", "drive": "hd0"}}
-{ "execute": "device_del", "arguments": {"id": "scsi-hd0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi-hd0", "driver": "scsi-hd", "drive": "hd0"}}
-{ "execute": "device_del", "arguments": {"id": "scsi-hd0"}}
-{ "execute": "device_del", "arguments": {"id": "scsi0"}}
-{ "execute": "blockdev-del", "arguments": {"node-name": "hd0"}}
-{ "execute": "quit"}
-EOF
-
-echo
-echo === Attach two SCSI disks using the same block device and the same iothread ===
-echo
-
-run_qemu <<EOF
-{ "execute": "qmp_capabilities" }
-{ "execute": "blockdev-add", "arguments": {"driver": "null-co", "read-zeroes": true, "node-name": "hd0", "read-only": true}}
-{ "execute": "object-add", "arguments": {"qom-type": "iothread", "id": "iothread0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi0", "driver": "${virtio_scsi}", "iothread": "iothread0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi-hd0", "driver": "scsi-hd", "drive": "hd0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi-hd1", "driver": "scsi-hd", "drive": "hd0"}}
-{ "execute": "device_del", "arguments": {"id": "scsi-hd0"}}
-{ "execute": "device_del", "arguments": {"id": "scsi-hd1"}}
-{ "execute": "device_del", "arguments": {"id": "scsi0"}}
-{ "execute": "blockdev-del", "arguments": {"node-name": "hd0"}}
-{ "execute": "quit"}
-EOF
-
-echo
-echo === Attach two SCSI disks using the same block device but different iothreads ===
-echo
-
-run_qemu <<EOF
-{ "execute": "qmp_capabilities" }
-{ "execute": "blockdev-add", "arguments": {"driver": "null-co", "read-zeroes": true, "node-name": "hd0", "read-only": true}}
-{ "execute": "object-add", "arguments": {"qom-type": "iothread", "id": "iothread0"}}
-{ "execute": "object-add", "arguments": {"qom-type": "iothread", "id": "iothread1"}}
-{ "execute": "device_add", "arguments": {"id": "scsi0", "driver": "${virtio_scsi}", "iothread": "iothread0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi1", "driver": "${virtio_scsi}", "iothread": "iothread1"}}
-{ "execute": "device_add", "arguments": {"id": "scsi-hd0", "driver": "scsi-hd", "drive": "hd0", "bus": "scsi0.0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi-hd1", "driver": "scsi-hd", "drive": "hd0", "bus": "scsi1.0"}}
-{ "execute": "device_del", "arguments": {"id": "scsi-hd0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi-hd1", "driver": "scsi-hd", "drive": "hd0", "bus": "scsi1.0"}}
-{ "execute": "device_del", "arguments": {"id": "scsi-hd1"}}
-{ "execute": "device_del", "arguments": {"id": "scsi0"}}
-{ "execute": "device_del", "arguments": {"id": "scsi1"}}
-{ "execute": "blockdev-del", "arguments": {"node-name": "hd0"}}
-{ "execute": "quit"}
-EOF
-
-echo
-echo === Attach a SCSI disks using the same block device as a NBD server ===
-echo
-
-run_qemu <<EOF
-{ "execute": "qmp_capabilities" }
-{ "execute": "blockdev-add", "arguments": {"driver": "null-co", "read-zeroes": true, "node-name": "hd0", "read-only": true}}
-{ "execute": "nbd-server-start", "arguments": {"addr":{"type":"unix","data":{"path":"$SOCK_DIR/nbd"}}}}
-{ "execute": "nbd-server-add", "arguments": {"device":"hd0"}}
-{ "execute": "object-add", "arguments": {"qom-type": "iothread", "id": "iothread0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi0", "driver": "${virtio_scsi}", "iothread": "iothread0"}}
-{ "execute": "device_add", "arguments": {"id": "scsi-hd0", "driver": "scsi-hd", "drive": "hd0", "bus": "scsi0.0"}}
-{ "execute": "quit"}
-EOF
-
-# success, all done
-echo "*** done"
-rm -f $seq.full
-status=0
+import iotests
+import os
+
+nbd_sock = iotests.file_path('nbd.sock', base_dir=iotests.sock_dir)
+
+class TestCase(iotests.QMPTestCase):
+    test_driver = "null-co"
+
+    def required_drivers(self):
+        return [self.test_driver]
+
+    @iotests.skip_if_unsupported(required_drivers)
+    def setUp(self):
+        self.vm = iotests.VM()
+        self.vm.launch()
+
+    def tearDown(self):
+        self.vm.shutdown()
+
+    def test1(self):
+        iotests.log('==Unplug a SCSI disk and then plug it again==')
+        self.vm.qmp_log('blockdev-add', driver='null-co', read_zeroes=True, node_name='hd0')
+        self.vm.qmp_log('object-add', qom_type='iothread', id="iothread0")
+        self.vm.qmp_log('device_add', id='scsi0', driver=iotests.get_virtio_scsi_device(), iothread='iothread0')
+        self.vm.qmp_log('device_add', id='scsi-hd0', driver='scsi-hd', drive='hd0')
+        self.vm.qmp_log('device_del', id='scsi-hd0')
+        self.vm.event_wait('DEVICE_DELETED')
+        self.vm.qmp_log('device_add', id='scsi-hd0', driver='scsi-hd', drive='hd0')
+        self.vm.qmp_log('device_del', id='scsi-hd0')
+        self.vm.event_wait('DEVICE_DELETED')
+        self.vm.qmp_log('device_del', id='scsi0')
+        self.vm.qmp_log('blockdev-del', node_name='hd0')
+
+    def test2(self):
+        iotests.log('==Attach two SCSI disks using the same block device and the same iothread==')
+        self.vm.qmp_log('blockdev-add', driver='null-co', read_zeroes=True, node_name='hd0', read_only=True)
+        self.vm.qmp_log('object-add', qom_type='iothread', id="iothread0")
+        self.vm.qmp_log('device_add', id='scsi0', driver=iotests.get_virtio_scsi_device(), iothread='iothread0')
+
+        self.vm.qmp_log('device_add', id='scsi-hd0', driver='scsi-hd', drive='hd0')
+        self.vm.qmp_log('device_add', id='scsi-hd1', driver='scsi-hd', drive='hd0')
+        self.vm.qmp_log('device_del', id='scsi-hd1')
+        self.vm.event_wait('DEVICE_DELETED')
+        self.vm.qmp_log('device_del', id='scsi-hd0')
+        self.vm.event_wait('DEVICE_DELETED')
+        self.vm.qmp_log('device_del', id='scsi0')
+        self.vm.qmp_log('blockdev-del', node_name='hd0')
+
+    def test3(self):
+        iotests.log('==Attach two SCSI disks using the same block device but different iothreads==')
+
+        self.vm.qmp_log('blockdev-add', driver='null-co', read_zeroes=True, node_name='hd0', read_only=True)
+
+        self.vm.qmp_log('object-add', qom_type='iothread', id="iothread0")
+        self.vm.qmp_log('object-add', qom_type='iothread', id="iothread1")
+
+        self.vm.qmp_log('device_add', id='scsi0', driver=iotests.get_virtio_scsi_device(), iothread='iothread0')
+        self.vm.qmp_log('device_add', id='scsi1', driver=iotests.get_virtio_scsi_device(), iothread='iothread1')
+
+        self.vm.qmp_log('device_add', id='scsi-hd0', driver='scsi-hd', drive='hd0', bus="scsi0.0")
+        self.vm.qmp_log('device_add', id='scsi-hd1', driver='scsi-hd', drive='hd0', bus="scsi1.0")
+
+        self.vm.qmp_log('device_del', id='scsi-hd0')
+        self.vm.event_wait('DEVICE_DELETED')
+        self.vm.qmp_log('device_add', id='scsi-hd1', driver='scsi-hd', drive='hd0', bus="scsi1.0")
+
+        self.vm.qmp_log('device_del', id='scsi-hd1')
+        self.vm.event_wait('DEVICE_DELETED')
+
+        self.vm.qmp_log('device_del', id='scsi1')
+        self.vm.qmp_log('device_del', id='scsi0')
+
+        self.vm.qmp_log('blockdev-del', node_name='hd0')
+
+    def test4(self):
+        iotests.log('==Attach a SCSI disks using the same block device as a NBD server==')
+
+        self.vm.qmp_log('blockdev-add', driver='null-co', read_zeroes=True, node_name='hd0', read_only=True)
+
+        self.vm.qmp_log('nbd-server-start',
+                        filters=[iotests.filter_qmp_testfiles],
+                        addr={'type':'unix', 'data':{'path':nbd_sock}})
+
+        self.vm.qmp_log('nbd-server-add', device='hd0')
+
+        self.vm.qmp_log('object-add', qom_type='iothread', id="iothread0")
+        self.vm.qmp_log('device_add', id='scsi0', driver=iotests.get_virtio_scsi_device(), iothread='iothread0')
+        self.vm.qmp_log('device_add', id='scsi-hd0', driver='scsi-hd', drive='hd0')
+
+
+if __name__ == '__main__':
+    if 'null-co' not in iotests.supported_formats():
+        iotests.notrun('null-co driver support missing')
+    iotests.activate_logging()
+    iotests.main()
diff --git a/tests/qemu-iotests/240.out b/tests/qemu-iotests/240.out
index d00df50297..24847be6b3 100644
--- a/tests/qemu-iotests/240.out
+++ b/tests/qemu-iotests/240.out
@@ -1,67 +1,83 @@
-QA output created by 240
-
-=== Unplug a SCSI disk and then plug it again ===
-
-Testing:
-QMP_VERSION
-{"return": {}}
+==Unplug a SCSI disk and then plug it again==
+{"execute": "blockdev-add", "arguments": {"driver": "null-co", "node-name": "hd0", "read-zeroes": true}}
 {"return": {}}
+{"execute": "object-add", "arguments": {"id": "iothread0", "qom-type": "iothread"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"driver": "virtio-scsi-pci", "id": "scsi0", "iothread": "iothread0"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"drive": "hd0", "driver": "scsi-hd", "id": "scsi-hd0"}}
 {"return": {}}
+{"execute": "device_del", "arguments": {"id": "scsi-hd0"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"drive": "hd0", "driver": "scsi-hd", "id": "scsi-hd0"}}
 {"return": {}}
+{"execute": "device_del", "arguments": {"id": "scsi-hd0"}}
 {"return": {}}
+{"execute": "device_del", "arguments": {"id": "scsi0"}}
 {"return": {}}
+{"execute": "blockdev-del", "arguments": {"node-name": "hd0"}}
 {"return": {}}
+==Attach two SCSI disks using the same block device and the same iothread==
+{"execute": "blockdev-add", "arguments": {"driver": "null-co", "node-name": "hd0", "read-only": true, "read-zeroes": true}}
 {"return": {}}
-
-=== Attach two SCSI disks using the same block device and the same iothread ===
-
-Testing:
-QMP_VERSION
+{"execute": "object-add", "arguments": {"id": "iothread0", "qom-type": "iothread"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"driver": "virtio-scsi-pci", "id": "scsi0", "iothread": "iothread0"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"drive": "hd0", "driver": "scsi-hd", "id": "scsi-hd0"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"drive": "hd0", "driver": "scsi-hd", "id": "scsi-hd1"}}
 {"return": {}}
+{"execute": "device_del", "arguments": {"id": "scsi-hd1"}}
 {"return": {}}
+{"execute": "device_del", "arguments": {"id": "scsi-hd0"}}
 {"return": {}}
+{"execute": "device_del", "arguments": {"id": "scsi0"}}
 {"return": {}}
+{"execute": "blockdev-del", "arguments": {"node-name": "hd0"}}
 {"return": {}}
+==Attach two SCSI disks using the same block device but different iothreads==
+{"execute": "blockdev-add", "arguments": {"driver": "null-co", "node-name": "hd0", "read-only": true, "read-zeroes": true}}
 {"return": {}}
+{"execute": "object-add", "arguments": {"id": "iothread0", "qom-type": "iothread"}}
 {"return": {}}
+{"execute": "object-add", "arguments": {"id": "iothread1", "qom-type": "iothread"}}
 {"return": {}}
-
-=== Attach two SCSI disks using the same block device but different iothreads ===
-
-Testing:
-QMP_VERSION
-{"return": {}}
-{"return": {}}
-{"return": {}}
-{"return": {}}
+{"execute": "device_add", "arguments": {"driver": "virtio-scsi-pci", "id": "scsi0", "iothread": "iothread0"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"driver": "virtio-scsi-pci", "id": "scsi1", "iothread": "iothread1"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"bus": "scsi0.0", "drive": "hd0", "driver": "scsi-hd", "id": "scsi-hd0"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"bus": "scsi1.0", "drive": "hd0", "driver": "scsi-hd", "id": "scsi-hd1"}}
 {"error": {"class": "GenericError", "desc": "Cannot change iothread of active block backend"}}
+{"execute": "device_del", "arguments": {"id": "scsi-hd0"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"bus": "scsi1.0", "drive": "hd0", "driver": "scsi-hd", "id": "scsi-hd1"}}
 {"return": {}}
+{"execute": "device_del", "arguments": {"id": "scsi-hd1"}}
 {"return": {}}
+{"execute": "device_del", "arguments": {"id": "scsi1"}}
 {"return": {}}
+{"execute": "device_del", "arguments": {"id": "scsi0"}}
 {"return": {}}
+{"execute": "blockdev-del", "arguments": {"node-name": "hd0"}}
 {"return": {}}
+==Attach a SCSI disks using the same block device as a NBD server==
+{"execute": "blockdev-add", "arguments": {"driver": "null-co", "node-name": "hd0", "read-only": true, "read-zeroes": true}}
 {"return": {}}
-
-=== Attach a SCSI disks using the same block device as a NBD server ===
-
-Testing:
-QMP_VERSION
-{"return": {}}
-{"return": {}}
+{"execute": "nbd-server-start", "arguments": {"addr": {"data": {"path": "SOCK_DIR/PID-nbd.sock"}, "type": "unix"}}}
 {"return": {}}
+{"execute": "nbd-server-add", "arguments": {"device": "hd0"}}
 {"return": {}}
+{"execute": "object-add", "arguments": {"id": "iothread0", "qom-type": "iothread"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"driver": "virtio-scsi-pci", "id": "scsi0", "iothread": "iothread0"}}
 {"return": {}}
+{"execute": "device_add", "arguments": {"drive": "hd0", "driver": "scsi-hd", "id": "scsi-hd0"}}
 {"return": {}}
-{"return": {}}
-*** done
+....
+----------------------------------------------------------------------
+Ran 4 tests
+
+OK
