Re: [Qemu-devel] [PATCH v2 11/19] s390x: allow only 1 CPU with TCG

[David Hildenbrand]

On 06.09.2017 23:20, Richard Henderson wrote:
> On 09/06/2017 11:16 AM, Matthew Rosato wrote:
>> On 09/04/2017 11:43 AM, David Hildenbrand wrote:
>>> Specifying more than 1 CPU (e.g. -smp 5) leads to SIGP errors (the
>>> guest tries to bring these CPUs up but fails), because we don't support
>>> multiple CPUs on s390x under TCG.
>>>
>>> Let's bail out if more than 1 is specified, so we don't raise people's
>>> hope. Make it a define, so we can easily bump it up later.
>>>
>>> Signed-off-by: David Hildenbrand <address@hidden>
>>> ---
>>
>> Makes sense.  Ran the described environment without this patch (errors)
>> and again with this patch (graceful exit w/ message).
>>
>> Tested-by: Matthew Rosato <address@hidden>
> 
> Can someone review
> 
>   http://patchwork.ozlabs.org/patch/760010/
> 

Yes, we also discovered that patch during review of v1.

> which does at least start to add the SIGP support.
> 
> Once tcg can bring up 2 cpus, I see no reason it couldn't bring up N.  I don't
> see the point of the define.
> 

Conny requested a define. So it boils down to

a) no define just as in v1
b) a define like S390_TCG_SMP_SUPPORTED

What do you suggest?

> 
> r~
> 


-- 

Thanks,

David