Re: [PULL 10/15] tests/functional: fix race in virtio balloon test

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 7/3/25 13:39, Thomas Huth wrote:
> On 07/03/2025 13.34, Philippe Mathieu-Daudé wrote:
>> Hi Thomas, Daniel,
>>
>> On 7/3/25 12:53, Thomas Huth wrote:
>>> From: Daniel P. Berrangé <berrange@redhat.com>
>>>
>>> There are two race conditions in the recently added virtio balloon
>>> test
>>>
>>>   * The /dev/vda device node is not ready
>>>   * The virtio-balloon driver has not issued the first stats refresh
>>>
>>> To fix the former, monitor dmesg for a line about 'vda'.
>>>
>>> To fix the latter, retry the stats query until seeing fresh data.
>>>
>>> Adding 'quiet' to the kernel command line reduces serial output
>>> which otherwise slows boot, making it less likely to hit the former
>>> race too.
>>>
>>> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
>>> Message-ID: <20250304183340.3749797-1-berrange@redhat.com>
>>> Reviewed-by: Thomas Huth <thuth@redhat.com>
>>> Reviewed-by: David Hildenbrand <david@redhat.com>
>>> [thuth: Break long line to avoid checkpatch error]
>>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>>> ---
>>>   tests/functional/test_virtio_balloon.py | 26 ++++++++++++++++++++-----
>>>   1 file changed, 21 insertions(+), 5 deletions(-)
>>
>> This fix isn't really working, and is more of band-aid IIUC.
>>
>> With the following patch restricting to KVM accel, do we still want it 
>> merged?
> 
> Yes, I think it still makes this test more robust.

Fine then, thanks.