diff --git a/tests/qemu-iotests/224 b/tests/qemu-iotests/224
new file mode 100755
index 0000000000..b4dfaa639f
--- /dev/null
+++ b/tests/qemu-iotests/224
@@ -0,0 +1,139 @@
+#!/usr/bin/env python
+#
+# Test json:{} filenames with qemu-internal BDSs
+# (the one of commit, to be precise)
+#
+# Copyright (C) 2018 Red Hat, Inc.
+#
+# 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; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will 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, see .
+#
+# Creator/Owner: Max Reitz
+
+import iotests
+from iotests import log, qemu_img, qemu_io_silent, filter_qmp_testfiles, \
+ filter_qmp_imgfmt
+import json
+
+# Need backing file support (for arbitrary backing formats)
+iotests.verify_image_format(supported_fmts=['qcow2', 'qcow', 'qed'])
+iotests.verify_platform(['linux'])
+
+
+# There are two variations of this test:
+# (1) We do not set filter_node_name. In that case, the commit_top
+# driver should not appear anywhere.
+# (2) We do set filter_node_name. In that case, it should appear.
+#
+# This for loop executes both.
+for filter_node_name in False, True:
+ log('')
+ log('--- filter_node_name: %s ---' % filter_node_name)
+ log('')
+
+ with iotests.FilePath('base.img') as base_img_path, \
+ iotests.FilePath('mid.img') as mid_img_path, \
+ iotests.FilePath('top.img') as top_img_path, \
+ iotests.VM() as vm:
+
+ assert qemu_img('create', '-f', iotests.imgfmt,
+ base_img_path, '64M') == 0
+ assert qemu_img('create', '-f', iotests.imgfmt, '-b', base_img_path,
+ mid_img_path) == 0
+ assert qemu_img('create', '-f', iotests.imgfmt, '-b', mid_img_path,
+ top_img_path) == 0
+
+ # Something to commit
+ assert qemu_io_silent(mid_img_path, '-c', 'write -P 1 0 1M') == 0
+
+ vm.launch()
+
+ # Change the bottom-most image's backing file (to null-co://)
+ # to enforce json:{} filenames
+ vm.qmp_log('blockdev-add',
+ node_name='top',
+ driver=iotests.imgfmt,
+ file={
+ 'driver': 'file',
+ 'filename': top_img_path
+ },
+ backing={
+ 'node-name': 'mid',
+ 'driver': iotests.imgfmt,
+ 'file': {
+ 'driver': 'file',
+ 'filename': mid_img_path
+ },
+ 'backing': {
+ 'node-name': 'base',
+ 'driver': iotests.imgfmt,
+ 'file': {
+ 'driver': 'file',
+ 'filename': base_img_path
+ },
+ 'backing': {
+ 'driver': 'null-co'
+ }
+ }
+ },
+ filters=[filter_qmp_testfiles, filter_qmp_imgfmt])
+
+ # As long as block-commit does not accept node names, we have to
+ # get our mid/base filenames here
+ mid_name = vm.node_info('mid')['image']['filename']
+ base_name = vm.node_info('base')['image']['filename']
+
+ assert mid_name[:5] == 'json:'
+ assert base_name[:5] == 'json:'
+
+ # Start the block job
+ if filter_node_name:
+ vm.qmp_log('block-commit',
+ job_id='commit',
+ device='top',
+ filter_node_name='filter_node',
+ top=mid_name,
+ base=base_name,
+ speed=1,
+ filters=[filter_qmp_testfiles, filter_qmp_imgfmt])
+ else:
+ vm.qmp_log('block-commit',
+ job_id='commit',
+ device='top',
+ top=mid_name,
+ base=base_name,
+ speed=1,
+ filters=[filter_qmp_testfiles, filter_qmp_imgfmt])
+
+ vm.qmp_log('job-pause', id='commit')
+
+ # Get and parse top's json:{} filename
+ top_name = vm.node_info('top')['image']['filename']
+
+ vm.shutdown()
+
+ assert top_name[:5] == 'json:'
+ top_options = json.loads(top_name[5:])
+
+ if filter_node_name:
+ # This should be present and set
+ assert top_options['backing']['driver'] == 'commit_top'
+ # And the mid image is commit_top's backing image
+ mid_options = top_options['backing']['backing']
+ else:
+ # The mid image should appear as the immediate backing BDS
+ # of top
+ mid_options = top_options['backing']
+
+ assert mid_options['driver'] == iotests.imgfmt
+ assert mid_options['file']['filename'] == mid_img_path
diff --git a/tests/qemu-iotests/224.out b/tests/qemu-iotests/224.out
new file mode 100644
index 0000000000..23374a1d29
--- /dev/null
+++ b/tests/qemu-iotests/224.out
@@ -0,0 +1,18 @@
+
+--- filter_node_name: False ---
+
+{"execute": "blockdev-add", "arguments": {"backing": {"backing": {"backing": {"driver": "null-co"}, "driver": "IMGFMT", "file": {"driver": "file", "filename": "TEST_DIR/PID-base.img"}, "node-name": "base"}, "driver": "IMGFMT", "file": {"driver": "file", "filename": "TEST_DIR/PID-mid.img"}, "node-name": "mid"}, "driver": "IMGFMT", "file": {"driver": "file", "filename": "TEST_DIR/PID-top.img"}, "node-name": "top"}}
+{"return": {}}
+{"execute": "block-commit", "arguments": {"base": "json:{\"backing\": {\"driver\": \"null-co\"}, \"driver\": \"IMGFMT\", \"file\": {\"driver\": \"file\", \"filename\": \"TEST_DIR/PID-base.img\"}}", "device": "top", "job-id": "commit", "speed": 1, "top": "json:{\"backing\": {\"backing\": {\"driver\": \"null-co\"}, \"driver\": \"IMGFMT\", \"file\": {\"driver\": \"file\", \"filename\": \"TEST_DIR/PID-base.img\"}}, \"driver\": \"IMGFMT\", \"file\": {\"driver\": \"file\", \"filename\": \"TEST_DIR/PID-mid.img\"}}"}}
+{"return": {}}
+{"execute": "job-pause", "arguments": {"id": "commit"}}
+{"return": {}}
+
+--- filter_node_name: True ---
+
+{"execute": "blockdev-add", "arguments": {"backing": {"backing": {"backing": {"driver": "null-co"}, "driver": "IMGFMT", "file": {"driver": "file", "filename": "TEST_DIR/PID-base.img"}, "node-name": "base"}, "driver": "IMGFMT", "file": {"driver": "file", "filename": "TEST_DIR/PID-mid.img"}, "node-name": "mid"}, "driver": "IMGFMT", "file": {"driver": "file", "filename": "TEST_DIR/PID-top.img"}, "node-name": "top"}}
+{"return": {}}
+{"execute": "block-commit", "arguments": {"base": "json:{\"backing\": {\"driver\": \"null-co\"}, \"driver\": \"IMGFMT\", \"file\": {\"driver\": \"file\", \"filename\": \"TEST_DIR/PID-base.img\"}}", "device": "top", "filter-node-name": "filter_node", "job-id": "commit", "speed": 1, "top": "json:{\"backing\": {\"backing\": {\"driver\": \"null-co\"}, \"driver\": \"IMGFMT\", \"file\": {\"driver\": \"file\", \"filename\": \"TEST_DIR/PID-base.img\"}}, \"driver\": \"IMGFMT\", \"file\": {\"driver\": \"file\", \"filename\": \"TEST_DIR/PID-mid.img\"}}"}}
+{"return": {}}
+{"execute": "job-pause", "arguments": {"id": "commit"}}
+{"return": {}}
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index f701863cdb..b5ca63cf72 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -224,6 +224,7 @@
221 rw auto quick
222 rw auto quick
223 rw auto quick
+224 rw auto quick
225 rw auto quick
226 auto quick
227 auto quick