Re: [Qemu-devel] [PATCH v2 3/6] tests/device-plug: Add a simple PCI unplug request test

[David Hildenbrand <david@redhat.com>]

On 15.02.19 16:21, Thomas Huth wrote:
> On 15/02/2019 14.30, David Hildenbrand wrote:
>> The issue with testing asynchronous unplug requests it that they usually
>> require a running guest to handle the request. However, to test if
>> unplug of PCI devices works, we can apply a nice little trick on some
>> architectures:
>>
>> On system reset, x86 ACPI, s390x and spapr will perform the unplug,
>> resulting in the device of interest to get deleted and a DEVICE_DELETED
>> event getting sent.
>>
>> On s390x, we still get a warning
>>     qemu-system-s390x: -device virtio-mouse-pci,id=dev0:
>>     warning: Plugging a PCI/zPCI device without the 'zpci' CPU feature
>>     enabled; the guest will not be able to see/use this device
>>
>> This will be fixed soon, when we enable the zpci CPU feature always
>> (Conny already has a patch for this queued).
>>
>> Signed-off-by: David Hildenbrand <david@redhat.com>
>> ---
>>  tests/Makefile.include   |  4 ++
>>  tests/device-plug-test.c | 93 ++++++++++++++++++++++++++++++++++++++++
>>  2 files changed, 97 insertions(+)
>>  create mode 100644 tests/device-plug-test.c
> 
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> 
> BTW, have you spotted the qpci_unplug_acpi_device_test() in libqos
> already? Might be interesting for these kinds of tests, too - we use it
> in a couple of other tests already, though, so I'm not sure if we need
> additional tests with that...
> 

Cool, no I haven't! It's PCI only, something similar for CPU/memory
unplug on x86 would be interesting. I might be looking into that in the
future.

-- 

Thanks,

David / dhildenb