Race condition in qemu-iotests nbd 205?

Race condition in qemu-iotests nbd 205?

[Stefan Hajnoczi]

Hi Vladimir,
It looks like there is a race condition in qemu-iotests 205 when the
NBD server is shutting down:

+FAIL: test_remove_during_connect_safe_hard (__main__.TestNbdServerRemove)
+----------------------------------------------------------------------
+Traceback (most recent call last):
+ File "/builds/qemu-project/qemu/tests/qemu-iotests/205", line 149,
in test_remove_during_connect_safe_hard
+ self.assertExportNotFound('exp')
+ File "/builds/qemu-project/qemu/tests/qemu-iotests/205", line 63, in
assertExportNotFound
+ self.assert_qmp(result, 'error/desc', "Export 'exp' is not found")
+ File "/builds/qemu-project/qemu/tests/qemu-iotests/iotests.py", line
1246, in assert_qmp
+ self.assertEqual(result, value,
+AssertionError: "Export 'exp' is already shutting down" != "Export
'exp' is not found"
+- Export 'exp' is already shutting down
++ Export 'exp' is not found
+ : "error/desc" is "Export 'exp' is already shutting down", expected
"Export 'exp' is not found"

https://gitlab.com/qemu-project/qemu/-/jobs/14745043965#L328

I have not seen this CI failure before, so it might be rare and hard
to reproduce.

Stefan

Re: Race condition in qemu-iotests nbd 205?

[Daniel P. Berrangé]

On Mon, Jun 08, 2026 at 10:23:18AM -0400, Stefan Hajnoczi wrote:
> Hi Vladimir,
> It looks like there is a race condition in qemu-iotests 205 when the
> NBD server is shutting down:
> 
> +FAIL: test_remove_during_connect_safe_hard (__main__.TestNbdServerRemove)
> +----------------------------------------------------------------------
> +Traceback (most recent call last):
> + File "/builds/qemu-project/qemu/tests/qemu-iotests/205", line 149,
> in test_remove_during_connect_safe_hard
> + self.assertExportNotFound('exp')
> + File "/builds/qemu-project/qemu/tests/qemu-iotests/205", line 63, in
> assertExportNotFound
> + self.assert_qmp(result, 'error/desc', "Export 'exp' is not found")
> + File "/builds/qemu-project/qemu/tests/qemu-iotests/iotests.py", line
> 1246, in assert_qmp
> + self.assertEqual(result, value,
> +AssertionError: "Export 'exp' is already shutting down" != "Export
> 'exp' is not found"
> +- Export 'exp' is already shutting down
> ++ Export 'exp' is not found
> + : "error/desc" is "Export 'exp' is already shutting down", expected
> "Export 'exp' is not found"
> 
> https://gitlab.com/qemu-project/qemu/-/jobs/14745043965#L328
> 
> I have not seen this CI failure before, so it might be rare and hard
> to reproduce.

FYi, If you don't have time to investigate & fix it quickly, just
file a gitlab bug and then annotate the test cases / clases with:

 @iotests.skip_flaky("https://gitlab.com/qemu-project/qemu/-/work_items/NNN")

which will make the test be skipped in CI / locally, until someone
has time to look at it.

With regards,
Daniel
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