[4/4] iotests: Add regression test for issue 945

Commit Message

Hanna Czenczek April 27, 2022, 11:40 a.m. UTC

Create a VM with a BDS in an iothread, add -incoming defer to the
command line, and then export this BDS via NBD.  Doing so should not
fail an assertion.

Signed-off-by: Hanna Reitz <[e-mail]>
---
 .../tests/export-incoming-iothread            | 81 +++++++++++++++++++
 .../tests/export-incoming-iothread.out        |  5 ++
 2 files changed, 86 insertions(+)
 create mode 100755 tests/qemu-iotests/tests/export-incoming-iothread
 create mode 100644 tests/qemu-iotests/tests/export-incoming-iothread.out

Comments

Eric Blake April 27, 2022, 1:52 p.m. UTC | #1

On Wed, Apr 27, 2022 at 01:40:57PM +0200, Hanna Reitz wrote:
> Create a VM with a BDS in an iothread, add -incoming defer to the
> command line, and then export this BDS via NBD.  Doing so should not
> fail an assertion.
> 
> Signed-off-by: Hanna Reitz <[e-mail]>
> ---
>  .../tests/export-incoming-iothread            | 81 +++++++++++++++++++
>  .../tests/export-incoming-iothread.out        |  5 ++
>  2 files changed, 86 insertions(+)
>  create mode 100755 tests/qemu-iotests/tests/export-incoming-iothread
>  create mode 100644 tests/qemu-iotests/tests/export-incoming-iothread.out

The test looks sane, and appears to match the formula posted in issue
945.  When applying just patches 3-4 (skipping 1-2), './check
export-incoming-iothread' passed, but './check -qcow2
export-incoming-iothread' failed; so the image format is important.
And the failure was rather verbose, which is a GOOD thing - our
efforts to make the python framework point out abnormal exits is
working!

+WARNING:qemu.machine.machine:qemu received signal 6; command: "/home/eblake/qemu/build/tests/qemu-iotests/...
...
+Traceback (most recent call last):
+  File "/home/eblake/qemu/tests/qemu-iotests/tests/export-incoming-iothread", line 69, in test_export_add
+    result = self.vm.qmp('block-export-add', {
...
+  File "/home/eblake/qemu/python/qemu/qmp/qmp_client.py", line 463, in _reply
+    raise result
+qemu.qmp.qmp_client.ExecInterruptedError: Disconnected
+
+======================================================================
+ERROR: test_export_add (__main__.TestExportIncomingIothread)
+----------------------------------------------------------------------
+Traceback (most recent call last):
+  File "/home/eblake/qemu/python/qemu/machine/machine.py", line 533, in _soft_shutdown
+    self.qmp('quit')
...
+qemu.qmp.protocol.StateError: QMPClient is disconnecting. Call disconnect() to return to IDLE state.
+
+During handling of the above exception, another exception occurred:
+
+Traceback (most recent call last):
+  File "/home/eblake/qemu/python/qemu/machine/machine.py", line 554, in _do_shutdown
+    self._soft_shutdown(timeout)
...
+  File "/home/eblake/qemu/python/qemu/qmp/protocol.py", line 968, in _readline
+    raise EOFError
+EOFError
+
+The above exception was the direct cause of the following exception:
+
+Traceback (most recent call last):
+  File "/home/eblake/qemu/tests/qemu-iotests/tests/export-incoming-iothread", line 54, in tearDown
+    self.vm.shutdown()
+  File "/home/eblake/qemu/python/qemu/machine/machine.py", line 583, in shutdown
+    self._do_shutdown(timeout)
+  File "/home/eblake/qemu/python/qemu/machine/machine.py", line 557, in _do_shutdown
+    raise AbnormalShutdown("Could not perform graceful shutdown") \
+qemu.machine.machine.AbnormalShutdown: Could not perform graceful shutdown
+
 ----------------------------------------------------------------------
 Ran 1 tests

-OK
+FAILED (errors=2)


Then applying patches 1-2 and repeating the test passed, so your test
is a good proof that we identified and fixed the problem at hand.

Reviewed-by: Eric Blake <[e-mail]>
Tested-by: Eric Blake <[e-mail]>

Given that it is visible with NBD, I'm happy to queue this series
through my tree if no one else grabs it first.

Patch

diff --git a/tests/qemu-iotests/tests/export-incoming-iothread b/tests/qemu-iotests/tests/export-incoming-iothread
new file mode 100755
index 0000000000..7679e49103
--- /dev/null
+++ b/tests/qemu-iotests/tests/export-incoming-iothread
@@ -0,0 +1,81 @@ 
+#!/usr/bin/env python3
+# group: rw quick migration
+#
+# Regression test for issue 945:
+# https://gitlab.com/qemu-project/qemu/-/issues/945
+# Test adding an export on top of an iothread-ed block device while in
+# -incoming defer.
+#
+# Copyright (C) 2022 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 <http://www.gnu.org/licenses/>.
+#
+
+import os
+import iotests
+from iotests import qemu_img_create
+
+
+image_size = 1 * 1024 * 1024
+test_img = os.path.join(iotests.test_dir, 'test.img')
+node_name = 'node0'
+iothread_id = 'iothr0'
+
+nbd_sock = os.path.join(iotests.sock_dir, 'nbd.sock')
+
+
+class TestExportIncomingIothread(iotests.QMPTestCase):
+    def setUp(self) -> None:
+        qemu_img_create('-f', iotests.imgfmt, test_img, str(image_size))
+
+        self.vm = iotests.VM()
+        self.vm.add_object(f'iothread,id={iothread_id}')
+        self.vm.add_blockdev((
+            f'driver={iotests.imgfmt}',
+            f'node-name={node_name}',
+            'file.driver=file',
+            f'file.filename={test_img}'
+        ))
+        self.vm.add_incoming('defer')
+        self.vm.launch()
+
+    def tearDown(self):
+        self.vm.shutdown()
+        os.remove(test_img)
+
+    def test_export_add(self):
+        result = self.vm.qmp('nbd-server-start', {
+            'addr': {
+                'type': 'unix',
+                'data': {
+                    'path': nbd_sock
+                }
+            }
+        })
+        self.assert_qmp(result, 'return', {})
+
+        # Regression test for issue 945: This should not fail an assertion
+        result = self.vm.qmp('block-export-add', {
+            'type': 'nbd',
+            'id': 'exp0',
+            'node-name': node_name,
+            'iothread': iothread_id
+        })
+        self.assert_qmp(result, 'return', {})
+
+
+if __name__ == '__main__':
+    iotests.main(supported_fmts=['generic'],
+                 unsupported_fmts=['luks'], # Would need a secret
+                 supported_protocols=['file'])
diff --git a/tests/qemu-iotests/tests/export-incoming-iothread.out b/tests/qemu-iotests/tests/export-incoming-iothread.out
new file mode 100644
index 0000000000..ae1213e6f8
--- /dev/null
+++ b/tests/qemu-iotests/tests/export-incoming-iothread.out
@@ -0,0 +1,5 @@ 
+.
+----------------------------------------------------------------------
+Ran 1 tests
+
+OK