Re: [Qemu-devel] [PATCH] aarch64: raise max_cpus to 8

[Peter Maydell]

On 20 August 2014 16:08, Joel Schopp <address@hidden> wrote:
>
> On 08/19/2014 05:43 PM, Peter Maydell wrote:
>> On 19 August 2014 22:33, Joel Schopp <address@hidden> wrote:
>>> I'm running on a system with 8 cpus and it would be nice to have qemu
>>> support all of them.  The attached patch does that and has been tested.
>>>
>>> That said, I'm not sure if 8 is enough or if we want to bump this even 
>>> higher
>>> now before systems with many more cpus come along. 255 anyone?
>> 8 is the limit for a GICv2 system. But yes, we could have 8 CPUs
>> here; I think this was just copied over from the vexpress boards
>> (which have 4 because that hardware has 4.)
> So the question is do we want to wait for the GICv3 changes to be merged
> to bump this to 255?  If we do want to wait then applying my patch that
> bumps it to 8 is the right thing to do now.

I'm not currently aware of any GICv3 support patches for QEMU
(I know there is some kernel work); it's the view the guest sees
that matters, and for QEMU based guests that has to be v2
currently.

So yes, we should bump to 8 for now.

-- PMM