Re: [PATCH 0/5] KVM: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS and re-purpose it on x86

Christian Borntraeger
2021-11-16T08:16:17Z

Am 15.11.21 um 17:04 schrieb Vitaly Kuznetsov:
[...]
> or cap KVM_CAP_MAX_VCPUS value with num_online_cpus(), e.g.
>
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 6a6dd5e1daf6..1cfe36f6432e 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -585,6 +585,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> r = KVM_MAX_VCPUS;
> else if (sclp.has_esca && sclp.has_64bscao)
> r = KVM_S390_ESCA_CPU_SLOTS;
> + if (ext == KVM_CAP_NR_VCPUS)
> + r = min_t(unsigned int, num_online_cpus(), r);
> break;
> case KVM_CAP_S390_COW:
> r = MACHINE_HAS_ESOP;

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>

I think this is the better variant. Thanks.