Re: [Qemu-devel] [qemu-s390x] [PULL 2/2] iotests: simple mirror test with kvm on 1G image

[Christian Borntraeger <borntraeger@de.ibm.com>]

On 05.12.2018 17:09, Vladimir Sementsov-Ogievskiy wrote:
> 05.12.2018 18:52, Christian Borntraeger wrote:
>>
>>
>> On 05.12.2018 14:39, Vladimir Sementsov-Ogievskiy wrote:
>>> 05.12.2018 15:35, Christian Borntraeger wrote:
>>>>
>>>>
>>>> On 05.12.2018 13:00, Vladimir Sementsov-Ogievskiy wrote:
>>>>> 05.12.2018 12:01, Christian Borntraeger wrote:
>>>>>>
>>>>>>
>>>>>> On 05.12.2018 09:46, Kevin Wolf wrote:
>>>>>>> Am 05.12.2018 um 09:23 hat Christian Borntraeger geschrieben:
>>>>>>>>>>> +# prepare source image
>>>>>>>>>>> +qemu_img_create('-f', iotests.imgfmt, '-o', 'preallocation=metadata', disk,
>>>>>>>>>>> +                str(size))
>>>>>>>>>>> +
>>>>>>>>>>> +vm = QEMUMachine(iotests.qemu_prog)
>>>>>>>>>>> +vm.add_args('-machine', 'pc,accel=kvm')
>>>>>>>>
>>>>>>>> This (pc) clearly does not work on other architectures.
>>>>>>>> In addition to that, I also need to add -no-shutdown on s390 (see 068 for a similar case)
>>>>>>>
>>>>>>> Leaving out pc definitely makes sense, and the bug still reproduces for
>>>>>>> me without it.
>>>>>>>
>>>>>>> I don't understand the -no-shutdown, though. Already for 068, neither
>>>>>>> the code nor the commit message when it was added explain why this is
>>>>>>> needed.
>>>>>>>
>>>>>>> Can you turn this into a proper patch and add a comment why -no-shutdown
>>>>>>> is needed?
>>>>>>
>>>>>> I already sent this patch. The reason is that there is no BIOS in a classical sense
>>>>>> on s390x. If no bootable image (external kernel or from disk) is found, the small boot
>>>>>> bios loads a disabled wait PSW. The default action for that is then shutdown.
>>>>>>
>>>>>
>>>>> Is it an option for you just drop the whole line "vm.add_args('-machine', 'pc,accel=kvm')"?
>>>>> The problem without it for me was that gdb failed to produce full and nice backtrace, but
>>>>> test worked anyway
>>>>
>>>> In the commid message Vladimir said that kvm is necessary to trigger the problem.
>>>>
>>>
>>> No, I didn't)
>>>
>>> and it's in the comment:
>>> # 3. drop kvm and use iotests.VM() (maybe, because of qtest) (however, it still
>>> #    reproduces, if just drop kvm, but gdb failed to produce full backtraces
>>> #    for me)
>>
>> Ok, so I would be fine with completely dropping that line.
>>
>> the patch would then be
>>
>>
>>
>> "-machine pc" will not work all architectures. Lets fall back to the
>> default machine by not specifying anything for the machine.
>>
>> In addition we also need to specify -no-shutdown on s390 as qemu will
>> exit on guest shutdown. This happens when there is no kernel or bootable
>> disk on s390.
>>
>> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
>> ---
>>   tests/qemu-iotests/235 | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/tests/qemu-iotests/235 b/tests/qemu-iotests/235
>> index da044ed34e..329da8f0c2 100755
>> --- a/tests/qemu-iotests/235
>> +++ b/tests/qemu-iotests/235
>> @@ -49,7 +49,8 @@ qemu_img_create('-f', iotests.imgfmt, '-o', 'preallocation=metadata', disk,
>>                   str(size))
>>   
>>   vm = QEMUMachine(iotests.qemu_prog)
>> -vm.add_args('-machine', 'pc,accel=kvm')
>> +if iotests.qemu_default_machine == 's390-ccw-virtio':
>> +        vm.add_args('-no-shutdown')
>>   vm.add_args('-drive', 'id=src,file=' + disk)
>>   vm.launch()
>>   
>>
>>
>> Shall I resend a v2?
>>
> 
> so, we need -no-shutdown even if we drop kvm? I hoped that not.. Hmm. grep points only to one iotest doing the same about no-shutdown - 068..

Kevin, shall I send the above patch as v2?