Re: [Qemu-devel] [PULL 14/28] runstate: migration allows more transitions now

[Juan Quintela]

Wen Congyang <address@hidden> wrote:
> On 07/08/2015 07:06 PM, Juan Quintela wrote:
>> zhanghailiang <address@hidden> wrote:
>>> Hi,
>>>
>>> If testing migration with '-S' for qemu command line, (migrate
>>> directly without executing 'cont' command),
>>> qemu process in the destination will abort with the follow message:
>>>
>>> ERROR: invalid runstate transition: 'inmigrate' -> 'prelaunch'
>>> Aborted
>>>
>>> After the follow modification, it will be OK. Is this need to be fix ?
>> 
>> but this is a "werid" case. basically it means that
>> 
>> - we start on host A
>> - we start on host B (with -S)
>> - we migrate from A to B
>> - now we migrate from B to C without running at all on B
>> 
>> Or I am missing something?
>
> What about this bug? Should we fix it in qemu-2.4?

Is there any other scenary where it makes sense?  My understanding from
previous description is that we shouldn't allow migration in that state.
I can be convinced of the contrary if you told me of a valid scenary.

Please, more people chime in, one way or another.  It is not that I have
a strong opposition to it, just that I can't see the need.

Thanks, Juan.


>
> Thanks
> Wen Congyang
>
>> 
>> Later, Juan.
>> 
>> 
>>>
>>> --- a/vl.c
>>> +++ b/vl.c
>>> @@ -583,6 +583,7 @@ static const RunStateTransition
>>> runstate_transitions_def[] = {
>>>      { RUN_STATE_INMIGRATE, RUN_STATE_WATCHDOG },
>>>      { RUN_STATE_INMIGRATE, RUN_STATE_GUEST_PANICKED },
>>> +    { RUN_STATE_INMIGRATE, RUN_STATE_PRELAUNCH },
>>>
>>>      { RUN_STATE_INTERNAL_ERROR, RUN_STATE_PAUSED },
>>>      { RUN_STATE_INTERNAL_ERROR, RUN_STATE_FINISH_MIGRATE },
>>>
>>>
>>> Thanks,
>>> zhanghailiang
>>>
>>> On 2015/7/7 21:08, Juan Quintela wrote:
>>>> Next commit would allow to move from incoming migration to error happening 
>>>> on source.
>>>>
>>>> Should we add more states to this transition?  Luiz?
>>>>
>>>> Signed-off-by: Juan Quintela <address@hidden>
>>>> Reviewed-by: Dr. David Alan Gilbert <address@hidden>
>>>> ---
>>>>   vl.c | 8 +++++++-
>>>>   1 file changed, 7 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/vl.c b/vl.c
>>>> index fec7e93..19a8737 100644
>>>> --- a/vl.c
>>>> +++ b/vl.c
>>>> @@ -573,8 +573,14 @@ static const RunStateTransition 
>>>> runstate_transitions_def[] = {
>>>>       { RUN_STATE_DEBUG, RUN_STATE_RUNNING },
>>>>       { RUN_STATE_DEBUG, RUN_STATE_FINISH_MIGRATE },
>>>>
>>>> -    { RUN_STATE_INMIGRATE, RUN_STATE_RUNNING },
>>>> +    { RUN_STATE_INMIGRATE, RUN_STATE_INTERNAL_ERROR },
>>>> +    { RUN_STATE_INMIGRATE, RUN_STATE_IO_ERROR },
>>>>       { RUN_STATE_INMIGRATE, RUN_STATE_PAUSED },
>>>> +    { RUN_STATE_INMIGRATE, RUN_STATE_RUNNING },
>>>> +    { RUN_STATE_INMIGRATE, RUN_STATE_SHUTDOWN },
>>>> +    { RUN_STATE_INMIGRATE, RUN_STATE_SUSPENDED },
>>>> +    { RUN_STATE_INMIGRATE, RUN_STATE_WATCHDOG },
>>>> +    { RUN_STATE_INMIGRATE, RUN_STATE_GUEST_PANICKED },
>>>>
>>>>       { RUN_STATE_INTERNAL_ERROR, RUN_STATE_PAUSED },
>>>>       { RUN_STATE_INTERNAL_ERROR, RUN_STATE_FINISH_MIGRATE },
>>>>
>> 
>> .
>>