Re: [Qemu-devel] [PULL 00/22] QOM CPUState patch queue 2015-07-06

[Bharata B Rao]

On Tue, Jul 7, 2015 at 7:55 AM, Peter Crosthwaite
<address@hidden> wrote:
> On Mon, Jul 6, 2015 at 5:24 PM, Andreas Färber <address@hidden> wrote:
>> Am 07.07.2015 um 01:13 schrieb Andreas Färber:
>>> Hello Peter,
>>>
>>> This is my QOM CPU patch queue. Please pull.
>>>
>>> Note: For time reasons I did not give this queue as much testing as usual,
>>> in particular BSD and non-x86 KVM hosts were not covered.
>>>
>>> Regards,
>>> Andreas
>>>
>>> Cc: Peter Maydell <address@hidden>
>>>
>>> Cc: Eduardo Habkost <address@hidden>
>>> Cc: Peter Crosthwaite <address@hidden>
>>>
>>> The following changes since commit 7edd8e4660beb301d527257f8e04ebec0f841cb0:
>>>
>>>   Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into 
>>> staging (2015-07-06 14:03:44 +0100)
>>>
>>> are available in the git repository at:
>>>
>>>   git://github.com/afaerber/qemu-cpu.git tags/qom-cpu-for-peter
>>>
>>> for you to fetch changes up to 116382f1504d655a1afdf3eac18d276a200428b7:
>>>
>>>   disas: cris: QOMify target specific disas setup (2015-07-06 22:36:17 
>>> +0200)
>>>
>>> ----------------------------------------------------------------
>>> QOM CPUState and X86CPU
>>>
>>> * Further QOM'ification of CPU initialization
>>> * Propagation of CPUState arguments and elimination of ENV_GET_CPU() usage
>>> * cpu_set_pc() abstraction
>>> * CPUClass::disas_set_info() hook
>>>
>>> ----------------------------------------------------------------
>> [...]
>>
>> Self-nack, hurry is never good:
>>
>>   /aarch64/qom/xlnx-ep108:
>> qemu-system-aarch64: Trying to use more CPUs than allowed max of 1
>> Broken pipe
>> FAIL
>>
>> Peter C., any ideas why this is regressing?
>>
>
> This:
>
> +    if (cpu >= max_cpus) {
> +        error_setg(errp, "Trying to use more CPUs than allowed max of %d\n",
> +                    max_cpus);
> +        return -1;
>
> xlnx-ep108 doesn't care about the -smp argument, it creates all 6 CPUs
> regardless of -smp. This is because the number of CPUs is not flexible
> in reality. It is also a heterogeneous arch (with R5s abd A53s) so
> trying to limit the grand total of CPUs is ambiguous (do you remove
> a53s or r5s for -smp < 6?).
>
> Can this check be dropped or is this a bug in xlnx where we should
> overcome by just forcing smp_cpus = 6 at machine level?

That check is needed to fail CPU realization when an attempt is made
to relialize (eg. via hotplug) more than allowed max number of CPUs.

Regards,
Bharata.