[PATCH v5 21/21] KVM: ARM64: Add a new kvm ARM PMU device

[Marc Zyngier]

On 07/12/15 14:37, Shannon Zhao wrote:
> 
> 
> On 2015/12/7 21:56, Marc Zyngier wrote:
>>> +static int kvm_arm_pmu_set_attr(struct kvm_device *dev,
>>>> +				struct kvm_device_attr *attr)
>>>> +{
>>>> +	switch (attr->group) {
>>>> +	case KVM_DEV_ARM_PMU_GRP_IRQ: {
>>>> +		int __user *uaddr = (int __user *)(long)attr->addr;
>>>> +		int reg;
>>>> +
>>>> +		if (get_user(reg, uaddr))
>>>> +			return -EFAULT;
>>>> +
>>>> +		if (reg < VGIC_NR_SGIS || reg >= VGIC_NR_PRIVATE_IRQS)
>>>> +			return -EINVAL;
>>>> +
>>>> +		return kvm_arm_pmu_set_irq(dev->kvm, reg);
>> What prevents the IRQ to be changed while the VM is already running?
>> This should probably be a one-shot thing (change it once, be denied
>> other changes).
> 
> So add a helper like vgic_initialized to check whether vPMU is initialized?

Something like that, yes.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...