Re: [PATCH v4 2/6] hw/arm/virt: Add a control for the the highmem redistributors

[Marc Zyngier <maz@kernel.org>]

Hi Eric,

On Mon, 10 Jan 2022 15:35:44 +0000,
Eric Auger <eric.auger@redhat.com> wrote:
> 
> Hi Marc,
> 
> On 1/7/22 5:33 PM, Marc Zyngier wrote:

[...]

> > @@ -190,7 +191,8 @@ static inline int virt_gicv3_redist_region_count(VirtMachineState *vms)
> >  
> >      assert(vms->gic_version == VIRT_GIC_VERSION_3);
> >  
> > -    return MACHINE(vms)->smp.cpus > redist0_capacity ? 2 : 1;
> > +    return (MACHINE(vms)->smp.cpus > redist0_capacity &&
> > +            vms->highmem_redists) ? 2 : 1;
> If we fail to use the high redist region, is there any check that the
> number of vcpus does not exceed the first redist region capacity.
> Did you check that config, does it nicely fail?

I did, and it does (example on M1 with KVM):

$ /home/maz/vminstall/qemu-hack -m 1G -smp 256 -cpu host -machine virt,accel=kvm,gic-version=3,highmem=on -nographic -drive if=pflash,format=raw,readonly=on,file=/usr/share/AAVMF/AAVMF_CODE.fd
qemu-hack: warning: Number of SMP cpus requested (256) exceeds the recommended cpus supported by KVM (8)
qemu-hack: warning: Number of hotpluggable cpus requested (256) exceeds the recommended cpus supported by KVM (8)
qemu-hack: Capacity of the redist regions(123) is less than number of vcpus(256)

Thanks,

	M.

-- 
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