Re: [PATCH 3/3] KVM: s390: use kvm->created_vcpus

[Cornelia Huck]

On Mon, 13 Jun 2016 15:25:32 +0200
Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:

> The new created_vcpus field avoids possible races between enabling
> capabilities and creating VCPUs.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
>  arch/s390/kvm/kvm-s390.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 

> @@ -426,7 +426,7 @@ static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *att
>  		ret = -EBUSY;
>  		VM_EVENT(kvm, 3, "%s", "ENABLE: CMMA support");
>  		mutex_lock(&kvm->lock);
> -		if (atomic_read(&kvm->online_vcpus) == 0) {
> +		if (kvm->created_vcpus) {

if (!kvm->created_vcpus) {

>  			kvm->arch.use_cmma = 1;
>  			ret = 0;
>  		}
> @@ -467,7 +467,7 @@ static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *att
> 
>  		ret = -EBUSY;
>  		mutex_lock(&kvm->lock);
> -		if (atomic_read(&kvm->online_vcpus) == 0) {
> +		if (kvm->created_vcpus) {

dito

>  			/* gmap_alloc will round the limit up */
>  			struct gmap *new = gmap_alloc(current->mm, new_limit);
>